Astronomy Cast

You can only describe a black hole by its mass and its spin. And maybe it’s charge. But allow us to propose a new criteria: the personal experience. Some black holes have seen things… Experienced the laws of physics at their most extreme. And today we’ll tell their stories. The more of the sky we observe, the more bizarre situations we find black holes in. Let’s explore!

Show Notes

• AI space content quality problem
• Star–black hole interaction behind SN 2023ZXD
• How BH–core mergers can trigger supernovae
• Accretion beyond the Eddington limit (e.g., LID568, ~40×)
• Mass gap challenges (e.g., GW231123 intermediate-mass BHs)
• Recoil kicks/ejected BHs (e.g., GW190412, ~50 km/s)
• BH size extremes: IGR J17091 to ~36-billion-M☉ candidate
• Primordial black holes: formation & detection prospects
• Early-universe BH/galaxy formation: mergers + direct collapse
• Science evolves: new data reshapes theories

Transcript

Fraser Cain: 

Welcome to Astronomy Cast, our weekly facts-based journey through the cosmos, where we help you understand not only what we know, but how we know what we know. I’m Fraser Cain, I’m the publisher of Universe Today. With me as always is Dr. Pamela Gay, a senior scientist for the Planetary Science Institute and the director of Cosmic Quest. Hey, Pamela, how are you doing?

Dr. Pamela Gay: 

I am doing well. I’m trying very hard not to burst out laughing at all the stuff our audience members are sticking in the chat, because right before we went live, we were talking about AI slop, and some of it is so bad, you can laugh or cry, and I usually do both. Both is a good answer.

Fraser Cain: 

Yeah, the recommendation that I make is go open up Chrome, open up a new incognito window, go to YouTube, do a search for whatever space topic is interesting to you, comets, space, James Webb, whatever, and you will see the sloppiest slop that ever slopped. And it is just, this is what YouTube is now showing to people when they come to their website, and not more legitimate science. So, what are you going to do?

You can only describe a black hole by its mass and its spin, and maybe its charge, but allow us to propose a new criteria, their personal experience. Some black holes have seen things, experienced the laws of physics at their most extreme, and today, will tell their stories. All right, you’ve got a bunch of stories queued up that are extreme black holes experiencing extreme experiences.

What’s your first one?

Dr. Pamela Gay: 

So, this is my so far favorite story of the year. A young 30 solar mass star was hanging out with its more massive previously sibling and made the mistake of consuming its sibling, which was a black hole at this point.

Fraser Cain: 

Right. So, what was the sort of series of events that led up to this, I guess, unfortunate mistake?

Dr. Pamela Gay: 

Right. So, the two stars were born with very different masses. The one started its life with about 30 solar masses.

The other one was significantly larger. We’re not sure how much larger because mass loss is a thing. But however big it started out, it ended up making a 10 solar mass black hole.

So, we have a binary system with a 10 solar mass black hole and a 30 solar mass regular everyday star. And due to drag forces, they were getting closer and closer to one another. And the 30 solar mass star made the unfortunate mistake of consuming that 10 solar mass black hole, which led to the black hole rapidly feeding on the contents of the star, the star changing in brightness over time.

And ultimately, the core of the star and the black hole together triggering one heck of a weird supernova. This object is Supernova 2023 ZXD. When they looked at its light curve, its light curve didn’t behave over time the way you would expect.

They went back through archival data, saw the system had been brightening over several years. And the research paper that came out of this is a spectacular example of, could it be this? Probably not because of this.

Could it be this? Probably not because of this. As they work through idea after idea.

And the thing that fit was star 8’s black hole, which is the opposite of what we’re used to. But at 30 solar masses, it was definitely the dominant player in the system.

Fraser Cain: 

Yeah. Yeah. I think our title on universe today, the story was star eats black hole and instantly regrets it.

Dr. Pamela Gay: 

Yeah. We had very similar for EVSN.

Fraser Cain: 

Yeah.

Dr. Pamela Gay: 

It’s my favorite story this year. Maybe my favorite in many years.

Fraser Cain: 

Yes. Just gloriously wrong. And so what do we think would have happened?

Like, you know, we, back in the day there was the star, the star with 30 times the mass of the sun. And then there was a much bigger star.

Dr. Pamela Gay: 

Yeah.

Fraser Cain: 

It died first because the more massive you are, the shorter your life.

Dr. Pamela Gay: 

Right.

Fraser Cain: 

Detonated as a supernova and left a black hole remnant. And now you’ve got this binary star system. And then the two got closer and closer and closer until the black hole went into the star.

Dr. Pamela Gay: 

Yeah, that is exactly what happened. And it all comes down to the fact that, yeah, the black hole was definitely nibbling on its companion as frictional forces brought them closer and closer together. But once it’s inside that atmosphere, it’s definitely a merger event.

And it’s definitely the blue star, which has gotten stirred up and bloated out a little bit, doing the consuming. And while that black hole inside the 30 mass star is going nom, nom, nom, nom, nom, nom on everything around it, it took time for the core and the black hole to merge and explode as a supernova.

Fraser Cain: 

And what caused the explosion? Like, why did it go supernova? And why did the black hole not just gobble up the star from within and disappear it?

Dr. Pamela Gay: 

It all comes down to the rates at which things can happen. So the 30 solar mass star, which was no longer 30 solar masses, to be clear, mass loss also did it in. It had a core that was already fairly evolved.

It was already on its way to going supernova at some point in its future. And the black hole simply accelerated the process. So the black hole itself couldn’t eat all of its surroundings fast enough to prevent a supernova.

What it could do is begin that core collapse process that prevented further nuclear reactions from going on. A star is carefully balanced between gravity trying to compress the entire situation, light pressure pushing out, trying to keep the star being a star. But the second you don’t have all the nuclear reactions you need going on in the core, the outer layers of the star are no longer supported by light and they’re going to collapse down.

As they collapse down, the higher densities that they get just because they’re now becoming a crumpled ball of star, those higher densities allow new nuclear reactions to go on, which explode out light, creating the supernova we see. So it’s this process of you kill what’s going on in the core, the light shuts off, everything collapses, generates new light that supernovas out the outermost layers while the core collapses to form whatever it forms in the end.

Fraser Cain: 

All right, what have you got next?

Dr. Pamela Gay: 

Oh man, there are so many different things to choose from and I’m just not going to get through nearly as many as I wanted. So I’m going to talk about LID568. This is a black hole in a dwarf galaxy that is feeding at rates a star should not be feeding at.

So there’s this thing called the Eddington limit and it is how we say black holes should be limited in what they should do. The idea is that as material tries to stream in, it gets hot, it gets dense, it generates light. This is a recurring theme in the universe.

That light then pushes out the material, preventing further infall, cutting off the feeding frenzy the black hole is experiencing.

Fraser Cain: 

Right, and this is the same kind of limit that we see with stars. We don’t see stars that have a billion times the mass of the sun. We see stars with about a hundred times the mass of the sun at the most and that’s because as they get bigger, hotter, more radiation, at a certain point they’re just blowing away any other material that’s going to try to fall into them and they just can’t get any bigger.

And black holes can do the same thing with the accretion disk that builds up around them.

Dr. Pamela Gay: 

But for reasons that my read-through of the discovery paper didn’t see an answer to, this thing is feeding at 40 times the Eddington limit.

Fraser Cain: 

Right.

Dr. Pamela Gay: 

And so suddenly we are discovering that black holes are capable, in some circumstances, of consuming material much faster and more thoroughly in a rapid, sudden epoch of growth than what we had expected. And researchers are actually thinking this particular star got all grown up in essentially one massive feeding frenzy that broke the limits we’d previously attempted to put on these things.

Fraser Cain: 

Yeah. There was a couple of interesting things about this story. So they said, using this idea of the Eddington limit, they said, well, if you sort of rolled this black hole back to the beginning of when it formed shortly after the beginning of the universe, it would have had to have formed from a star that was about 10,000 times the mass of the sun was one option.

The other option is that it was a direct collapse black hole, that it just went straight into from cloud of gas and dust to black hole and then grew from there. And those would help you explain a black hole that you saw with this kind of size. But the sort of really interesting idea is that there are ways that black holes can maybe cool themselves down, that they can actually allow inflows of material that gets around this Eddington limit by artificially cooling the regions around them as well.

So there’s a lot of, you know, obviously the universe can do things that are weirder than we had ever anticipated. And this just shows like your theories are great, but at a certain point, you know, reality has some lessons to explain to us.

Dr. Pamela Gay: 

And this idea that black holes can form at masses that a stellar mass star going straight into a black hole can’t explain is something that comes up over and over again. So another example of things behaving weirdly is a LIGO discovery GW231123, which is beautifully symmetric. This particular paper had 10 and a half pages of authors.

I just want to call out collaborations are amazing and sometimes eat a lot of papers. So don’t print those things out. This particular merger was between a 103 and a 137 solar mass black hole.

So this is two intermediate mass black holes merging together into a larger intermediate mass black hole. And the thing about this is both of the black holes that went into the merger fell in what was supposed to be a gap in black holes formed through stars. What happens is as a star gets bigger and bigger and bigger, it eventually reaches the point where the core completely combusts the entire system.

This pair instability means that at lower masses, sure, it collapses down, has a black hole in the core. At higher masses, it can overcome this. Sure, collapses down, becomes a black hole again.

But in this gap, when it tries to do that, the helium in the core is like, I’m not going to have anything to do with that. And it explodes completely. So here we have a system.

Fraser Cain: 

There’s like no remnant, no black hole, nothing.

Dr. Pamela Gay: 

There’s nothing, nothing left behind, all gone. And here we have a system with two black holes that both fall into the black hole mass gap. And the question becomes, were we completely wrong on the mass gap?

Is there another mechanism for forming black holes? Or is this a statistically improbable system that was able to go from two things that formed black holes that merged, two things that formed black holes that merged, and then those black holes merged to get this eventual outcome? And the statistics on how hard would it be to get that double black hole binary system that forms, so you start out with a system of four black holes, and then you ultimately end up with one.

How difficult is that? And it’s not entirely improbable, but it’s at least 25% possible and 75% improbable. So probably not.

We’re learning black holes do not follow the rules, people. They do not care.

Fraser Cain: 

And we talked about a similar story, I feel like within the last year, same situation. Although one of the black holes shouldn’t have been. The other one was fine, but one of them was in that mass gap.

And so the fact that we’ve seen now two of them, maybe more, I’m not sure exactly how many LIGO has seen, is showing that either this theory that black holes aren’t formed from this certain mass of black holes, or that there’s some other mechanism. And the one that’s really exciting, which would also explain the previous story, is that you have primordial black holes. So you have black holes that were formed early on in the universe of any mass, some that were the mass of an asteroid, some that were the mass of a billion times the mass of the sun.

And then you can have any mass you like be able to meet with each other and merge. And you’re not dependent on that process of stars forming bigger black holes, meeting other black holes, meeting other black holes, and eventually building up that chain of events to get the kind of collisions that we’re seeing.

Dr. Pamela Gay: 

And this is one of those things where, again, I think the answer is going to be both. That we’re going to realize that, yes, there were primordial black holes, and there’s no other really good way to explain all the stuff JWST is finding in the early universe. That we’re going to realize that, in many cases, you have giant blobs of material that collapse straight into a black hole thanks to turbulence and other cooling factors that are able to take place.

It’s just like what we’ve found with galaxies. It used to be that people thought we were going to one day realize that it was either a hierarchical merging of smaller systems into progressively larger systems, or that it was clouds of gas that collapsed down into the size we see generally. And it turns out the answer is both.

That early in the universe, there were massive elliptical galaxies that formed, but there were also hierarchical growth that led to things like spiral galaxies we live in.

Fraser Cain: 

All right. What’s your next example?

Dr. Pamela Gay: 

So we’ve been talking a lot about massive black holes because, I mean, we all love massive black holes, but we’re starting to find small black holes. Now, neutron stars can’t, for questionable values of can’t, be larger than 2.25 solar masses because above that, the neutron degeneracy pressure can’t support the star and it collapses. Now, there’s always people who are moving that limit up or down by tuning different parameters in the system.

But around 2.25 solar masses is where the limit in the size of neutron stars is. And in looking at stellar mass black holes, there appears to be this gap where there’s like nothing around three or four solar masses. And it’s not entirely clear why there’s nothing in this particular mass range.

But we’re starting to find smaller systems. One of these is G3425. It has a mass that looks to be around 3.8 solar masses. It’s definitely beneath four solar masses. And it looks like part of the way it got that way was through having jets. So we need to figure out how do you take a truly massive object, have it collapse, leave behind only its core, and in the process, shed enough material that you end up with just the right size of a tiny core.

Fraser Cain: 

Wow. And so was this happening like as it was forming?

Dr. Pamela Gay: 

Yeah.

Fraser Cain: 

Huh. Very cool. I’ve got a story up here and let me know if this is in your list.

GW190412, the recoil event.

Dr. Pamela Gay: 

No, that one I don’t have anymore.

Fraser Cain: 

All right. All right.

Dr. Pamela Gay: 

The universe is big.

Fraser Cain: 

Yeah. So this is a black hole that was discovered in 2019 between two black holes. One was eight times the mass of the sun.

The other one was four times the mass of the sun. And this is one of the largest discrepancies in masses between two black holes. You had one that was double the mass of the other one.

And so the question that the astronomers were wondering was, would you get a recoil? Would you get a kick because you had this big difference between the black holes? And so they were able to sort of carefully examine the collision in the LIGO data and determined that, yes, indeed, after these black holes came together, because their masses were so different, it was kind of like a thruster on the side of the finished black hole that then gave it a kick at about 50 kilometers per second to the side.

So it was just because it was asymmetrical, as the black holes came together, then you got this kick, this recoil. And it happened inside a globular cluster. And so the recoil was enough to kick the black hole out of the globular cluster.

And so one of the big expectations is that the place to look for intermediate mass black holes is in these globular clusters, that you’ve got a lot of stars. They’re very close together. A lot of them were massive.

They died, became black holes, black holes merged, and so on. But they have found a few, but not as many as that they were expecting. And so now, maybe, over the course of enough time, a 50-kilometer-per-second kick is going to push your black hole right out of your cluster.

And so it might be that these black holes, they’re forming, if they’re not exactly equivalent masses, you’re going to get these kicks. These things are going to be spat out into the larger galaxy. And a lot of these globular clusters are outside of the plane of the galaxy.

And so they’re just spat out randomly into the universe.

Dr. Pamela Gay: 

Conservation of momentum is a bear. This is literally the black hole equivalent of what happens when, don’t do this with human beings, your AI-driven three-wheeler collides with your AI-driven SUV, and you end up going primarily in the direction of the SUV’s mass. Yeah.

Okay, that is impressive. So let’s look at the other extreme. This is my favorite discovery story of a black hole.

It wasn’t behaving badly. It was just behaving bigly, to use a word that I shouldn’t. Extremely, yeah.

Yeah. Hugely. Its distance is 5 billion light years.

Its mass is 36 billion solar masses. And it’s in the cosmic horseshoe galaxy. And what was happening is this really massive galaxy was getting used to study gravitationally lensed background objects.

And they were working to try and deconvolve what’s going on with all these gravitationally lensed things. And used the Hubble Space Telescope to do some very sophisticated observations of the core of the galaxy. And it was enough to be able to measure the motions of stars and gas down in the core of the galaxy and get the mass of the central black hole.

Normally, you can’t do this with any but the closest of the massive galaxies. But this black hole is so unbelievably large that even at 5 billion light years, they were able to use spectroscopy to measure velocities. And it’s just, yeah, it’s just awesome.

Accidental science is the best science sometimes.

Fraser Cain: 

Yeah. And I think a lot of people were listening to this episode. You’re familiar maybe with TON618, I think is the name of the black hole.

And that was largely considered the most massive black hole that’s ever been seen in that same kind of region. And now it looks like this new cosmic horseshoe is a serious contender, perhaps the winner of the most massive supermassive black hole in the universe that we’ve ever found.

Dr. Pamela Gay: 

It’s definitely the winner of the best discovery story for a massive black hole.

Fraser Cain: 

Right, right, right. But yeah, it is a contender for the most massive, the biggest. Check the Guinness Book of World Records shortly.

And that might be the black hole that’s in there. What else you got?

Dr. Pamela Gay: 

So that was really my list of favorites. Um, the star eating the black hole. I mean, there’s a few others out there.

Chandra found IGR J17091, which is a contender for being the smallest black hole. It’s somewhere between three and 10 solar masses looking closer to three than to 10, but they don’t have enough data to say for certain how tiny it is. And I just want to point out that we are now looking at things that are ranging from between IGR J17091 and G3425, which are both down around three solar masses.

And then the cosmic horseshoe galaxy central supermassive black hole, 36 billion solar masses. We’re looking at roughly a 10 billion solar mass factor, like multiplier of 10 billion between the smallest and the largest we’ve seen so far. And there’s absolutely no physical limit on how small or large a black hole can be.

The only limits are how do you form it? And, and this is where to get the small ones, we need to master mass loss to get the biggest ones. We need to master mass inflow and physics likes to break both of those things.

And so primordial gets us, okay, so what leftover small things are floating around our universe.

Fraser Cain: 

So speaking of that, um, I’ve got one last story then before we can close this out. And this is a prediction. So this idea of primordial black holes, we brought this up earlier.

One of the, if these things are out there, then it could have been formed at any mass and the, um, the smallest ones, the least massive ones will evaporate and have already evaporated. And so there is a sort of the smallest possible black hole in the universe is the one that is about to evaporate.

Dr. Pamela Gay: 

Yes.

Fraser Cain: 

And so people have, have done some calculations and that if this is happening, our modern neutrino observatories should, with about a 90% chance detect the presence of this last gasp. When a black hole evaporates, you get this sort of burst of high energy radiation neutrinos and that we now have detectors that are sensitive enough to find this. And so within about a decade, if, if this actually happens, we should detect the burst of a black hole evaporating.

And so that’ll tell us whether or not these primordial black holes exist.

Dr. Pamela Gay: 

And, and the only thing we have to remember is this could very well be like all the predictions of protons decaying, where we have these theories that say this thing should be happening and then we just never see it. And, and this is the reason we keep doing science is we are building a picture of a universe that when we create our science has to conform to everything we know is in the picture. It makes predictions about things that haven’t been seen yet, but until we see everything, which we’re never going to be able to do, we can’t fill in all the details and we’re going to periodically be wrong.

And that’s kind of awesome because that means there’s new physics waiting to be discovered.

Fraser Cain: 

I’m sure this will not be the last time we’ve done a story of an episode that is about this kind of thing that we’re going to find exoplanets, black holes, galaxies, things doing extreme things. Thanks, Pamela.

Dr. Pamela Gay: 

Thank you, Fraser. And thank you so much to everyone out there who is watching us live. And especially thanks to all of our patrons.

Thank you all so very much.

Fraser Cain: 

Sounds good. All right. Thanks, Pamela.

We’ll see you all next week.

Dr. Pamela Gay: 

Bye-bye.

Live Show

Your spacecraft has reached the end of its mission. You’ve done everything you can to keep it operational, but now it’s time to say goodbye. How do space agencies deal with spacecraft to shut them down gracefully, protect future missions and life on other worlds. So, the time has come to see your mission across the Rainbow Bridge. How exactly do you say goodbye? Let’s discuss. 

Show Notes

• Why Missions End
• End-of-Life (EOL) Planning
• Risks & Externalities
• Tech & Policy Outlook
• Underinvestment in EOL solutions—needs urgency.
• Space 101 Nuggets
• What’s Ahead

Transcript

Fraser Cain: AstronomyCast, Episode 766 How Spacecraft End. Welcome to AstronomyCast, your weekly facts-based journey through the Cosmos, where we help you understand not only what we know, but how we know what we know. I’m Fraser Cain, I’m the Publisher of Universe Today.

With me as always is Dr. Pamela Gay, a Senior Scientist for the Planetary Science Institute and the Director of CosmoQuest. Hey Pamela, how are you doing?

Dr. Pamela Gay: I am doing well. I have to point out for the audience, for those who don’t know because they only listen to the podcast, I come up with the initial graphics and name of it, and then you give it a much more SEO friendly, but this is one of those episodes where I’m super proud my title was End of Life Planning for your spacecraft. Yours more SEO friendly, mine amused me more, and I just need to share, you are the master of titles.

I am the person who writes hokey titles that amuse me.

Fraser Cain: Yeah, yeah. I mean, this is always a tension between us, and people wonder what is the core tension between Fraser and Pamela as a production duo here, is that I want the episodes to be very no-nonsense, as a standalone and different from the other stuff that we do, because both of us are doing much more whimsical, news-based, current events. That’s our bread and butter, and so this is something that is timeless, we’ll be here forever.

The episode about Mercury, it’s called Mercury, and so often what will happen is I will pitch you a whole bunch of subjects, and mine are very much gravitational lensing, spiral galaxies, and you will be on the deepness of thought regarding the- I don’t do that, I do usually plays on words. Yes, you are very punny, you are very lyrical in the way you describe these, and for me, like normally, yeah, I’m all over that, that sounds great, those are the kinds of titles that I would do, but for Astronomy Cast, it needs to be this archive of just very straightforward, easily accessible things. So this is a creative tension, and sometimes I win, sometimes you win, mostly neither of us care enough to make a big stink about it.

Your spacecraft has reached the end of its mission. You’ve done everything you can to keep it operational, but now it’s time to say goodbye. How do space agencies deal with spacecraft to shut them down gracefully, protect future missions and life on other worlds?

So what led to your thinking about this episode, because this topic came from you.

Dr. Pamela Gay: So basically, we first did, okay, so you need to get a launch license, then we looked at rockets versus the environment, and I was like, I’m out of creativity, is there anything else that naturally follows on that cycle? Well, once they’re born, they have to die, and that’s literally where this came from, was now that we’ve launched them, what do we do with them?

Fraser Cain: But there was a really dramatic mission end that happened earlier this year with the Gaia mission, and we got this sort of blow by blow explanation of what was going on, and I think a lot of people were quite puzzled by the extremes that the European Space Agency was going to, to shut down the Gaia mission. It wasn’t just, all right, we’re just going to leave it there, turn off the switches, hopefully we’ll come back in a couple of years and maybe somebody will be able to get Gaia going again, who knows?

Dr. Pamela Gay: No, no, no.

Fraser Cain: They went scorched earth on Gaia.

Dr. Pamela Gay: Yeah, they yeeted it into a heliocentric orbit.

Fraser Cain: And dismantled its memory block by block, overwriting it with garbage to make sure.

Dr. Pamela Gay: Now that I’m not sure they had to do, but.

Fraser Cain: Yeah, well, so the rationale for that was that they didn’t want this spacecraft to accidentally come back online and to interfere with any other missions that were going on. They wanted to not only be non-functional propellant-wise, power-wise, et cetera, because it still had lots of power, right? It just didn’t have the propellant.

And so they had to, it was going to, and it was built to be super redundant, really try hard to connect with earth-based satellite. It was really going to keep trying to do its mission. And so they had to go in and they had to rewrite its memory block by block, filling it with, I think the names of everybody on the team.

Imagine you just go through your memory of some software application you’ve worked on, replacing it block by block on the hard drive with the names of people. It is not going to be a functional piece of software by the time you’re done with it.

Dr. Pamela Gay: No.

Fraser Cain: Yeah.

Dr. Pamela Gay: No. No. And, and, and this really, when you think about how hardcore that is, like in my universe, sure.

You just like overwrite whatever the, the equivalent of the BIOS part of the memory is. But no, they did the whole darn thing.

Fraser Cain: Yeah. They did the whole thing. They made sure that there is no possible way that that spacecraft can lurch from the grave and interfere and that their concern about it messing up comms, providing a false signal was just so extreme that they went to this level of finality for the mission.

And, and this is the kind of thinking, like I wanted to start with this very dramatic example because this is the kind of headspace that mission planners are in. And I think that for a lot of people that is going to feel very surprising that the expectation is you’ve already spent all this money, all this time, all this expenditure to get this thing out into space. Why won’t they just leave it?

And then maybe some future generation could come along and use it and continue to bring it back operationally. So we’ll get to all of that. But let’s sort of just talk about this limited lifespan of satellites and spacecraft.

Dr. Pamela Gay: So we, we have two major things that, that bring spacecraft to a natural end, depending on how they’ve been constructed. One is you run out of propulsion, so you’re no longer able to change your orbit, lift your orbit, do whatever to your orbit. Now there are some spacecraft, they put them where they want them.

They are fine where they are. Let’s just leave them there. And even with those, you start to then run into the risk of, okay, so propulsion isn’t necessarily my problem, but they could hit something.

They could land on some buddy. They could land someplace that doesn’t currently have some buddies and put some buddies there. There, there are a whole variety of ways that your no longer fully functional mission could cause a very bad day for a planet where the earth is a planet or other spacecraft that are out there trying to live their best life.

Fraser Cain: And we see this happening about once a year where someone didn’t take the end of life for their spacecraft or their space station very seriously. And it’s going to come back down at a random location, almost certainly into the Pacific Ocean, but maybe just maybe into a populated center.

Dr. Pamela Gay: And we’ve also started to see a whole lot of near misses where they’ve had to radically move spacecraft. And at some point, as the number of spacecrafts continues to grow exponentially, it’s going to hit the point where we don’t just have near misses. We have actual collisions that create more massive debris clouds than anyone really wants to deal with.

Fraser Cain: Right. So we’ve got the situation like in low earth orbit, these things could potentially come back down to earth in random locations, even leaving them in low earth orbit. They’re going to be, it’s a very dense environment, relatively speaking, you know, still space, you know, it’s wide open, but still satellites do crash into each other and that if you leave your satellite, it’s going to potentially crash into others and you’re going to get more debris.

The debris is going to crash into more debris. You’ve got a problem. And then the issue that we mentioned with Gaia is that they can also be a, a communications hazard that they’re going to be, you know, there’s a limited amount of bandwidth.

You’ve got a guy over there screaming, give me a job. Let me give you something to do. I’m over here.

I mean, who among us? Yeah. I haven’t had to deal with that situation, but there’s one more issue with in the outer solar system.

We saw this with the Galileo mission and the Cassini mission. What’s that about?

Dr. Pamela Gay: And this is the concern of the spreading somebodies where the somebodies are microbes, bacteria, and other life forms that get carried out there from the planet earth. And we are learning more and more about worlds in the outer solar system that either in the past or continue to have sub ice oceans. And there is potentially transfer of materials through cracks, through processing from the surface down into those seas.

And we don’t want our life to potentially destroy life somewhere else or just make it so that we’re not sure if what we’re eventually finding came from us or got there on its own.

Fraser Cain: Yeah. I always use this example, right? We send the first life mission to Enceladus and they’re like, cyanobacteria, weird.

And then they, you know, they start to Europe and cyanobacteria, weird. And they were on Mars. Cyanobacteria, weird.

Cyanobacteria is everywhere. It’s all related. It’s all just from earth because cyanobacteria just loves an opportunity to take over.

All right. So we talked about sort of the reasons why spacecraft are that some level of intelligence needs to go into what you do with your spacecraft at the end. You don’t just walk away from your spacecraft.

You got to do something with it. So what do they do?

Dr. Pamela Gay: So there, there are a number of different ways to dispose of your spacecraft. And, and, uh, there’s actually international guidelines that when you have something in orbit around the earth, uh, per UN guidance, they make arrangements with different other organizations. Uh, 25 years after your mission is over, your spacecraft should be put somewhere safe.

The FAA has upgraded that now that we have so many more things out there to five years, you have five years to dispose of your spacecraft people. And so what they’re looking at is let’s put solar sails on it. Let’s put drag systems on it.

Let’s do something with those low earth orbit satellites that allow us to make sure with certainty that atmospheric drag is able to deorbit them with things that are further out. Uh, we lift them up into higher orbits or as they did with Gaia, send them on a journey round the sun. And remember it is energetically easier to remove something from the solar system than to crash it into the sun.

So don’t ever try and crash anything into the sun unless you’re trying to study the sun.

Fraser Cain: Yeah. Uh, yeah, I think, I think it’s really important to go over this because we get this question all the time, which is like, why don’t they just crash spacecraft into the sun? Um, and you, and you gotta know, like if you ever say like, why don’t they just, then you know already there’s a really good reason why they don’t just, you just, you just don’t know the why yet.

And that is because the sun is actually the most difficult place to reach in the entire solar system that the earth is orbiting around the sun at 30 kilometers per second. And the only way to make your material actually crash into the sun is to cancel out that 30 kilometers per second of orbital momentum. Thirty kilometers per second is faster than any spacecraft has ever been launched from earth.

It would require propulsion systems that are unyet dreamed of. We literally cannot make a spacecraft crash into the sun. And I defy you, play Kerbal Space Program, make a spacecraft go into the sun.

You will realize how difficult and challenging a problem this is only through multiple flybys of Mercury and Venus slingshot maneuvers. Can you finally get something into the sun that things don’t drift off into the sun in space? We’re at the bottom of a mountain and to get up to the lunar orbit, you have to climb a mountain to get from earth orbit to the sun.

You have to climb a different mountain or backwards. I don’t know. Anyway, that moving spacecraft dramatically far away from where they currently are requires expenditures of propulsion that is way beyond what it took to even just launch the spacecraft in the first place.

So you got to deal with what you got.

Dr. Pamela Gay: Yeah. Momentum is the law. It is going to be conserved.

You have to transfer it somewhere.

Fraser Cain: Yeah. So you mentioned this idea that they put it somewhere. Can you describe these sort of parking orbits or sort of what’s the term they’ve got them for the ones at?

Graveyard orbits. Yeah. Graveyard orbits.

Dr. Pamela Gay: Yeah. So with geostationary satellites, there is a set altitude where when you’re at that distance from the earth and in a circular orbit, key is circular orbit, you go around and around the world every 24 hours, which means that if you’re planted directly over the equator, you stay over the exact same place in orbit. If you are north or south tilted, you would clearly be both north and south tilted depending on where you are in the orbit.

You’re going to go up and down a single line of longitude and geostationary orbits are super useful for communication, super useful for weather satellites. And while it is a huge orbit because it’s so far away from the earth, there’s still squabbling over space. And so when something is no longer in use, they boost it to a higher orbit.

The idea being it’s in a higher orbit, it’s now, it’s going to get out of sync with staying over the same place. It’s going to actually be orbiting in more than 24 hours at that point, but atmospheric drag is not going to pull it back down to the earth because higher, safer, less stuff. And so they just stick stuff in parking orbits with the idea that maybe someday someone will go out with their junk collector, the walleys of the future in orbit, and start scooping these missions up to do whatever we decide to do with them in the future.

That works for things in geostationary orbit. Gaia was out in a Lagrange point and that is another place that has the potential to get super crowded because we really like to put things there. Now luckily the Lagrange points are only semi-stable.

It doesn’t take very much energy to get yourself out of this balancing point where the gravity of the sun, the gravity of the earth keeps you balanced so that the earth and that Lagrange point go around the sun at the same period. It’s different rates, you’re at different distances from the sun. So if you’re on the inner Lagrange point, you’re going to be going slower to keep pace with the earth.

If you’re further out, you’re going to be going faster. But it’s really easy to remove yourself from those semi-stable points. And as Gaia did, just put yourself into your own solitary orbit around the sun that allows the earth and your dead self to meet every few months, I guess.

Fraser Cain: But it’s more than that, it’s that you have to expend energy to remain at the Lagrange It’s true, yeah. So you just stop, and this works well, if you no longer have propulsion, then you’re no longer able to remain at the Lagrange point, you are going to naturally drift. And then if you do have a little bit of propulsion left, you can sort of decide where you’re going to drift.

Dr. Pamela Gay: But it’s self-cleaning. They really want you to remove yourself though. So the issue with allowing things to yeet themselves, I just love that word by the way, is you don’t know what you’re going to hit on the way out if you’re not steering.

And this is the difference between you and I both sledded as kids, and some sleds you can steer because they have little blades on them, and others you just sort of lean and hope. And a spacecraft doesn’t even have the ability to lean and hope as it allows either the atmosphere or just instability to move it over time. So the idea is you have a controlled exit from that orbit you should no longer stay in within five years of end of mission.

And while you’re still under control, we don’t want any out of control spacecraft if we can help it. They expect this to only be a 90% success rate. It’s spacecraft.

Space is hard. But the goal is 90% within five years for US spacecraft. The rest of the world is more like, we’ll give it 25.

That’s where we are.

Fraser Cain: So we’ve talked about how you sort of deal with spacecraft here around Earth. But we saw a very interesting decision made for Galileo and Cassini. So how did that operate?

Dr. Pamela Gay: So with Cassini is referred to as the grand finale. This was back in 2017. NASA made this a massive press event.

They actually asked me to delay launch of a bunch of my programs because they didn’t want my little tiny programs to potentially distract from Cassini’s attention. Cassini was a flagship mission that gathered gigabytes and gigabytes of data at a time when gigabytes were new and phenomenally large before we entered the terabyte and petabyte world of today. And the thing about this grand finale was this was a mission that had been extended such that they were able to capture the entirety of seasons of Saturn as it went around the sun.

And we didn’t know that would be something we could do. They were able to evolve the orbit to get closer and closer to the surface and study the clouds in detail. But at the Saturn system, you have Titan, which is a methane-ethane world that we know because of Cassini has lakes and deltas.

The Huygens probe was able to catch amazing imagery of this. And this is all the stuff of life. These are carbon molecules.

And with so many organics at Titan and the recognition that the chemistry of its atmosphere is out of equilibrium in ways that require either active geological processes, active biological processes, or both, both is allowed, Titan is a world we don’t want to mess with. We want to allow it to be its special little amazing self, even though we already dropped Huygens on it. So we didn’t want to crash there.

We know that Enceladus is another one of these ocean worlds with its tiger stripes. We didn’t want to mess with things there. And so that meant we had to dispose of our spacecraft somewhere where we weren’t worried about Earth life being compatible.

And the atmosphere of Saturn and plunging through it to the high density, extreme temperatures of going through that atmosphere seemed like a really good way to dispose of a spacecraft while not risking contamination. So that is exactly what they did back in 2017.

Fraser Cain: Yeah. And I think, you know, that again, seems kind of weird to people, you know, like, why are you keeping it around? And it’s just that you can’t predict the future chaotic movements of the spacecraft as they continue to orbit around the planets and their moons.

That crashing into one of those moons is kind of inevitable. If you run the math into the future, and so, you know, it may take thousands of years, tens of thousands of years, but eventually it’s probably going to crash into one of the moons or crash into Jupiter or get into weird orbits through body interactions. So as we kind of get close to closing out this episode, I think it’s important to say that these ideas about end of life, you sort of mentioned it briefly that, you know, people are looking at putting drag shoots, putting various other methods of slowing spacecraft down and that this is actually a very under-invested, like people aren’t taking this seriously yet.

And that there are committees coming together for the European Space Agency and international groups that are trying to put some kind of regulation that all spacecraft must have an end of life plan. And this is not the case today. So right now you can launch a spacecraft and people are going to say, look, what are you going to do when this thing reached the end of its operations?

You’re like, I don’t know. Who cares? Right.

And that’s perfectly no longer acceptable. Well, it is. I mean, like nobody is going to take it a task yet, but we’re probably just a couple of years away from that being the case that there are zero debris, zero remnant policies that are being put together now by especially the European Space Agency.

Dr. Pamela Gay: The Kessler syndrome is something we truly wish to avoid. The WALL-E future is not the one I want. And unless it’s only the cute robots, I’m happy to take the cute robots and leave all of the death and destruction behind.

Fraser Cain: Who can gently push away satellites as they fly out into space, as opposed to the reality where they’re moving at 28,000 kilometers per hour and are like bullets tearing things apart.

Dr. Pamela Gay: So, yeah, we want to avoid the Kessler syndrome. We want to avoid landing things on people’s houses. There is amazing statistics that if the current growth of satellites goes up, we’re going to start to see human beings getting hit on the decade scale of time.

And just like clean up after yourselves, people. Leave nothing but footprints, take nothing but pictures.

Fraser Cain: Space footprints. Yeah.

Dr. Pamela Gay: Yeah.

Fraser Cain: Yeah. I mean, it’s like, again, it’s another tragedy of the comets that we are knowingly stumbling ourselves into, that we have this resource space. It is incredibly useful for us to be able to do our operations down here on Earth.

You can be able to communicate, be able to navigate, learn about the weather, predict, see our impact on the environment. It goes on and on. Farmers to track their fields, there’s so many benefits from us having this resource of space.

And yet, like we always do, we are filling it and not thinking too deeply about how to share it as a space. And we’re already starting to experience some consequences, but they have not gotten bad yet. We are in the pre-consequence phase of this process.

And now is the time to think about how to deal with it.

Dr. Pamela Gay: And it’s going to be an amazing future. And I look forward to doing an update on this, where we talk more about the new technologies to refuel, to grab and move, to de-orbit forcefully.

Fraser Cain: Oh, that sounds great. Yeah. Yeah.

Let’s, let’s, I mean, because it’s not just like you shut off your spacecraft and call it a day, that the kinds of things that people are yelling into their devices right now, why don’t they refuel them? Why don’t they refurbish them? This is all an industry that is starting to take off.

And in fact, various spacecraft have done this. So I think you’re exactly right. Let’s, let’s come back around in the future and talk about what are the cool ideas to deal with space junk, refurbish satellites, make them operational longer, try to live that dream of a, of a reusable, repairable future.

Dr. Pamela Gay: And we’ll be five years from now talking about how ISS is getting de-orbited. That is something like, I’m going to travel to see Apophis fly by. I’m going to travel to see YR4 potentially hit the moon.

And the ISS launching is going to be absolutely amazing.

Fraser Cain: Like seeing the ISS come down.

Dr. Pamela Gay: Yeah.

Fraser Cain: Yeah. Yeah. But I mean, it’ll be happening in the middle of the Pacific ocean, hopefully.

Hopefully. But yeah. All right.

We’ll see. Thanks, Pamela.

Dr. Pamela Gay: Thank you, Fraser. And thank you everyone out there. This show is supported by you through Patreon.

If you don’t have money to throw, we’re fine with that. Just go follow for free so that you can get regular updates on everything we’re doing. And I will be reading names separately, Rich, that file’s coming to you later today.

We are here thanks to the amazing support of everyone at Patreon.com slash AstronomyCast. This week, we would like to thank in particular Abraham Cottrell, Alex Cohen, Alexis, Andrew Palestra, Andy Moore, Arctic Fox, Brett Moorman, Brian Cook, Brian Kilby, Buzz Parsec, Claudia Mastroianni, Danny Maglucci, Diane Philippon, Fairchild, just as it sounds, Felix Gutt, G. Caleb Sexton, Gerhard Schweitzer, Glenn McDavid, Gordon Dewis, Helga Bjorkhag, J.

Alex Anderson, Janelle Jarvis-Earl, Jeanette Wink, Jim McGeehan, Joanne Mulvey, Jonathan H. Staver, Jordan Turner, Katie Barron, Katie and Ulyssa, Christian Golding, Lee Harbourn, Masa Hulehu, Matthew Crampton, Michael Purcell, Michelle Cullen, Mike Dogg, Noah Albertson, Paul Esposito, Paul L. Hayden, Peter, Planetar, Rajev Achari, Robbie the Dog with the Dot, Rizard with AZ, Sergio Sanchevo, Sachi Takeba, Skone, Scott Briggs, Stephen Coffey, The Lonely Sandperson, Tim Garish.

Thank you all so very much. We wouldn’t be here without you.

Fraser Cain:  Thanks everyone, and we will see you next week. Bye-bye.

Live Show

This week, we look at the process behind rockets getting licensed to launch, and everyone around the pad getting notified to stay away as T-0 approaches. (Can you say “errant boat”?) We have a saying around here: “One does not simply book a return trip from a rocket launch.” That’s because they are an intensely complex chain of events that need to go right before it’s wise to let that rocket leave the launchpad. 

Show Notes

• Rocket impacts
• Re-entry impacts
• Ozone
• Scale vs aviation
• Light pollution
• Wildlife
• Methane
• Atmospheric physics
• Launch growth
• Cadence plans
• Human tech & ecosystems
• Minimize harm
• Factor externalities in policy & economics
• CTA: Support research, responsible launch/sat policies, and dark-sky initiatives.

Transcript

Fraser Cain:   

AstronomyCast, Episode 765, Rockets vs. the Environment. Welcome to AstronomyCast, our weekly facts-based journey through the Cosmos, where we help you understand not only what we know, but how we know what we know.

I’m Fraser Cain, I’m the publisher of Universe Today. With me as always is Dr. Pamela Gay, Senior Scientist for the Planetary Science Institute, and the Director of CosmoQuest. Hey Pamela, how are you doing?

Dr. Pamela Gay: 

I am doing well. We are recording this on the fall equinox. It’s all downhill from here.

Fraser Cain:   

Yeah, yeah, we can feel it. The weather definitely, definitely changed. Things are cooler, the wind is up.

Hopefully the rain will return. We’re still waiting on any amount of rain here. It’s been five months now since we’ve had serious rainfall.

Yeah, everything is just parched. So, you know, deep into September, the wildfire warning is still pretty extreme. So hopefully we will get just a miserable storm that will just dump a ton of rain on us and reset us back to some level of normality.

Dr. Pamela Gay: 

I have to admit we are in that strange time of year in Southern Illinois where all of my morning glories are wildly blooming everywhere and the leaves are changing and I kind of dig the combination.

Fraser Cain:   

Like bindweed? Kill it with fire. The white flowers?

Dr. Pamela Gay: 

Little blue flowers. Little blue flowers.

Fraser Cain:   

All right, all right.

Dr. Pamela Gay: 

They’re good.

Fraser Cain:   

We don’t launch a lot of rockets every year, so their impact on the environment is minimal compared to other forms of transportation. But that number is steadily increasing with rates that we’ll have to take seriously. What’s the current and future impact of rockets on the environment?

So give us a sense of the environmental impact. I guess, what are the forms, what are the ways that rockets can harm the environment compared to, you know, other forms of transportation that we’re familiar with?

Dr. Pamela Gay: 

So we have a number of different things going on. We have both launch and return to consider.

Fraser Cain:   

Yeah.

Dr. Pamela Gay: 

And on the way up, we have the sonic boom, which can deeply confuse and disturb surrounding animals. We have, in the case of the way SpaceX does things, there is usually a cloud of very cold, formerly liquid gas that goes across the landscape, chilling everything in its path. We have, as the rockets go up through the atmosphere, depending on if they’re solid rocket or the liquid oxygen that is so popular, or methane, which is becoming popular, you’re putting gases into the atmosphere at altitudes they may not normally be at.

Fraser Cain:   

Yeah. And then not to mention solid rockets, which produce other kinds of chemicals, again, at different altitudes.

Dr. Pamela Gay: 

And then we have satellites falling back down through the atmosphere. Satellites now need to have a five years after they’re no longer planned to be used plan for how to get them out of the way of everything else. And that generally includes burning them up in the atmosphere.

That drops particulate matter into the upper part of the atmosphere, where we are not sure if the dominant factor is going to be increasing the reflectivity of the planet or increasing the ability of greenhouse effect as light that goes up gets re-radiated back down. We’re still figuring out that balance.

Fraser Cain:   

And there’s also damage to the ozone layer from those satellites.

Dr. Pamela Gay: 

Yes.

Fraser Cain:   

Burning up in the atmosphere.

Dr. Pamela Gay: 

And if something blows up, as Starship has done, it can actually put a hole in the ionosphere, which is fun.

Fraser Cain:   

And then there are rockets that don’t make it all the way up to space and they don’t burn up in the atmosphere. And instead, they crashed into the ocean. And so, for example, the Space Launch System is going to crash the first stage into the ocean and sink to the bottom of the ocean and break up.

But yeah, you’ve got the plume of steam, of hot steam that comes out from the water system that tries to deal with the noise from the rockets that is blown out across the landscape. So there’s a bunch of things that are happening. There’s then all of the transportation that’s required, all of the maintenance, all of the infrastructure that’s required to get a rocket ready to launch.

In some cases, rockets are taken, you know, they’re constructed in California and then they’re taken on train all the way across the United States or on truck to be able to get to the launch site in Florida. So you’ve got all the separate component parts that are all coming together to launch this rocket. And now at this point, I’m sure those of you who are concerned about our impact on the environment would like to get a sense of the scale.

So do we have a sense of like how much rockets contribute to damage to the environment?

Dr. Pamela Gay: 

So there are detailed studies coming out of the Environmental Protection Agency and the National Oceanographic and Atmospheric Administration that look at different factors. So for instance, my favorite thing that has been done so far is near Vandenberg is a beach where sea lions like to raise their young. And prior to allowing an ongoing launch license for SpaceX, which has far more launches out of Vandenberg than anyone else has had, they were required to monitor for a period of time how the sea lions reacted to sonic booms to make sure that the number of sea lions typically seen on the beach was not decreasing as an impact of having the sonic boom race across their beach.

There are also studies that look at what are the basically regions in which you’re going to have different amounts of sound, that chest vibrating noise that can actually cause damage to ears and what kinds of wildlife is within that. And so here they’re literally doing, okay, so we’ve seen this rocket go up. We know that it causes this many seabirds to just go away, cease to live within that region.

Fraser Cain:   

Yeah, don’t want to live there anymore.

Dr. Pamela Gay: 

Right. We know how much bigger the next rocket they’re planning to put is. Let’s now run calculations to model the decrease in seabirds and shoreline critters and alligators or something you have to worry about in Florida.

They go through and they look at all the different wildlife that is native to the area and that may decide it doesn’t want to live there anymore as a result of the impact of rockets. It turns out seabirds don’t care very much. They are seeing order of a few percent decreased, 10% decrease with bigger and bigger rockets.

The sea lions also do not seem to care very much. The biggest impact they’ve seen was a literal impact. It turns out that if you violently blow up the starship, you’re about to test the engines on for no clear reason.

I mean, they figured out the reason there was a starship that they were getting ready to test. One of the canisters became overpressured. The entire thing violently exploded and it shed pieces all over a beach where baby turtles were hatching.

And baby turtles can’t necessarily figure out how to go around pieces of exploded starship. So don’t explode your rockets was the primary thing.

Fraser Cain:   

Don’t explode your rockets. Don’t explode your rockets. But, and, and that is, I mean, there are, there are like, again, I think like if people, people are going to feel really mad about this environmental damage or even this environmental impact that you are making this place that is scary and undesirable for the homes, for various mammals and seabirds, uh, that you are going to disrupt the patterns of animals that have had their, you know, their evolutionary process, their instincts have led them to these places. And so they don’t, you know, they can’t, you know, pack up and move somewhere else that this is going to have an impact on them.

That said, I mean, highways that crisscross the, the country, which are just killing zones for animals that are attempting to migrate. Uh, if you, we drove in Australia and it is just dead kangaroo, dead kangaroo, just a graveyard of animals here in Canada. It’s deer, um, moose elk.

Dr. Pamela Gay: 

Armadillos. Armadillos are suicidal.

Fraser Cain:   

Yeah. Armadillos, turtles. So, uh, you know, there’s so much, you know, transportation, birds hitting the windows of your cars.

Like, like there are the, you know, the, what we do with mining, right. To a chunk of it. And so I think it’s great.

You know, we should definitely have a serious consideration about this, but you know, these are the kinds of concerns that animate you, uh, get, get out there and help work on minimizing humanity’s impact on the natural world because it is everywhere.

Dr. Pamela Gay: 

I do maintain you shouldn’t explode your rockets.

Fraser Cain:   

Yeah, well, obviously, but I mean like exploding rockets is not part of the plan. Exploding rockets is, is definitely part of the process and is definitely going to happen, but it is not the, you know, not every rocket is going to explode before the thing takes off from the, from the launch pad. So, you know, like the, like the, you know, this is a concern we actually didn’t talk about, which is light pollution.

Right. That, that, that there are star links that are passing through the night sky that if you look up now, if you could see the star links, there would be this giant grid. There would be hundreds of star links in the sky from your dozens, maybe dozens, but eventually it’ll be hundreds and that this is going to, you know, you can’t see it with your eyes, but they are contributing a generalized glow that is making satellite observations just a little bit harder.

Not to mention the ones that run directly through any imaging that a giant telescope is doing at certain times of the year. So there’s sort of like this increase in overall light pollution, the sky glow, as well as the direct harm. And, you know, people are very angry about this.

And yet a third of humanity can no longer see the Milky Way. Like the, our ability to see the sky has been completely taken from us because people can’t remember or can’t be bothered to use the kinds of lights that are best and point them towards the ground that we have to just point these things up in the sky and, and take away this, this view that is causing enormous harm to, uh, to animals that are tempted to migrate, et cetera.

Dr. Pamela Gay: 

It’s something where, again, we have to compare and contrast. So for instance, the World Trade Center Memorial lights, when they get turned on, they can’t leave them on for very long because birds will get stuck in them and just go in circles because they can’t figure out how to navigate once they’re in the light. But the satellite constellations are something that it’s important to understand how these things work.

They want to have multiple low altitude to decrease latency satellites overhead all the time. So ideally something like five satellites out at a time in your sky, this is on top of the GPS satellites that have to be there already per network. And it’s a per network issue.

Fraser Cain:   

Just like GPS is a per national collaboration, Chinese ones, you’re going to have the American ones, you’re going to have the European ones. They’re all going to be overhead.

Dr. Pamela Gay: 

And, and so as we layer orbit with more and more and more satellites to accomplish things with competing companies, it’s, it’s going to increase what we’re trying to look through. And then, and then there, there is this thing called reflect orbital. All of you go to reflect orbital.com at some point, they’re looking to build satellites that what they say on their website is reflect orbital is delivering sunlight by building a constellation of in space mirrors and, and they show solar panels at night receiving sunlight. And I really want this to be the onion, but they’re proudly saying they’ve secured 20 million in series a funding.

Fraser Cain:   

Yeah.

Dr. Pamela Gay: 

And, and so we’re also looking at a future where if someone wants to make sure that they’re all day, all night wedding celebration is well lit, you’d order up a satellite.

Fraser Cain:   

Right. All right. So we rattled off a bunch of atmospheric gases that are being delivered and they have different potentially battling impacts on the environment.

So let’s just start with the, the greenhouse gases.

Dr. Pamela Gay: 

Methane. Methane is the one that worries me the most. We’re looking to power more and more rockets with methane.

It is a, it is one of the most serious greenhouse gases out there and it does break down in sunlight. So when you release methane into the atmosphere, it’s not going to stay there for years. It’s going to stay there for months breakdown under UV.

But while it’s there, it is contributing to as infrared light tries to leave our planet. So sunlight comes through in all the colors of the rainbow and colors redder and bluer than what we can see in our eyes. All that light comes through.

It warms the surface of our planet. It warms the atmosphere around us and warm things re-radiate in infrared. It’s black body radiation.

Ideally, a lot of that heat energy then radiates back out into space. But just like a greenhouse you might build in your backyard where the glass serves to keep the infrared warm light, warm photons inside your greenhouse. Well, putting methane into our atmosphere keeps that infrared warm light within our atmosphere, continuing to keep our atmosphere warmer than it necessarily would have been in the past.

This leads to long term heat. So, okay, there’s methane. That’s one issue.

We worry about ozone. We worry about how ozone is getting broken down as they add other chemicals to the atmosphere. There is concern that increased launch activity is creating a new northern hemisphere ozone hole.

And ozone holes, as any Australian can let you know, increase how much ultraviolet light is able to come down through our atmosphere. So each of these different gases that goes into the atmosphere changes what light comes through the atmosphere and reflects back away from the planet.

Fraser Cain:   

Mm hmm.

Dr. Pamela Gay: 

Too much ultraviolet coming through due to holes in the ozone layer, reduction in the amount of ozone at the correct altitude in the atmosphere means more ultraviolet light and more cancers. And so we’re actually making ourselves sick by launching too many rockets that are depleting the ozone layer.

Fraser Cain:   

Right. But it’s really important to understand here that the amounts that are, the depletion is very low, right? Currently.

So there was a study that was done, we reported this earlier this year, that right now with the current launch rates of in the sort of 200 to 300 launches per year, that it’s not outpacing the restoration of the ozone layer based on the reduction of chlorofluorocarbons. But you get up to the about say 1200 rate rockets per year, which is not inconceivable, then those numbers flip. And now the amount of damage to the ozone layer is happening faster than the amount that the lack, you know, than the thing is repairing.

And so everything turns around and goes the other way. And the sweet spot, or I guess the target to look at is, it’s around the 700 launches ish per year, 750 launches per year. So as we get closer to that 750 launches per year, then we will start to sort of zero out the damage that we’re doing or the restoration of the ozone layer and start to move in the other direction.

And then the other thing, and like this is, you know, when you think about say carbon dioxide, one transatlantic flight is about the same amount of carbon dioxide produced as one rocket launch. And that one, you know, one rocket launch is going to, you know, how many, you know, you’re going to get a couple of hundred launches per year when you’re going to have, what, tens of thousands of flights a day, right? Thousands of flights a day.

Dr. Pamela Gay: 

So, so all of that is true, but one of the concerns is the altitude at which the gases are getting released.

Fraser Cain:   

And the, and the, the kind of, of, um, uh, the plume. So, so they’re very sooty. Yeah.

Rocket launches are very sooty. And so they produce a lot of fine particles that, as you say, are, are making their way into layers of the atmosphere that we’ve never seen that before. And that comes back to what you said earlier, which is that in fact, potentially we’re looking at, um, uh, potentially a cooling effect in sort of the same way that we had the, the shipping when they removed the sulfur dioxide from their fuels that actually things warmed up because they were these clouds, these persistent clouds of the shipping lanes were going away in the Atlantic.

So it’s like so confusing.

Dr. Pamela Gay: 

And the scale is really something that, that I, I have to give you actual numbers. It’s currently September 22nd. So far this year, we’ve had 222 launch attempts, according to rocket launch.live, um, eight of them ceased to be rockets prior to getting very high. So 2025, 222 at this point, looking back at 2020 in 2020 for the entire year, there were 114 looking back at 2015, there were 85 for the entire year. So we are going up very rapidly and they’re looking at adding dozens of launches per year of the Falcon 9 to Vandenberg. They’re looking to add order of 80 per pad Starship launches to, uh, Cape Canaveral.

I don’t know what numbers they’re aiming for, for, uh, Boca Chico. I haven’t read those reports yet. So we’re looking at with just one company, massive, massive increases in launches.

Now you start to propagate this across, you see Blue Origin is launching more and more of, of their smaller rockets. They’re starting to get their larger rockets going. You have Rocket Lab is just there slow and steady getting the job done.

And China is really working hard to catch up, uh, looking at launches by country. We’ve had 54 launches so far this year that were successful from China.

Fraser Cain:   

Yeah. So we talked about this and again, it’s very complicated and this is something that’s a lot of work on about the gases that are going out from the rocket as the thing is taking off. But you have the, the end of life and the most efficient way to deal with rockets with debris with satellites is to have them reenter the Earth’s atmosphere and that they are introducing very specific types of particles at an altitude that, that you don’t, don’t normally see.

That said, there is about a hundred tons of debris that is falling into the atmosphere every day from space.

Dr. Pamela Gay: 

Yeah.

Fraser Cain:   

But that is generally silicon oxide, iron oxide, you know, it is, it is chunks of rock.

Dr. Pamela Gay: 

Yeah. Yeah.

Fraser Cain:   

Not the kinds of exotic materials like aluminum, titanium, uh, the, the stuff that goes into solar panels. So it’s a different mix. What kind of impact are we expecting to see from these reentering satellites?

Dr. Pamela Gay: 

So one of the concerns is there’s a whole lot of aluminum used in space manufacturing. Uh, star, Starship by SpaceX is one of the exceptions. They’re using steel.

Most companies are using a lot of aluminum because it gives you a really good lightweight material that you can then use to support whatever the outer shell of your craft is. All that aluminum in the atmosphere appears to be the kind of particulate matter that’s capable of staying lofted in the atmosphere for long periods of time, which is a problem and then acting as a potential greenhouse gas feels like the wrong term to use, but I mean, it’s a greenhouse material that is changing the reflectivity of the atmosphere.

Fraser Cain:   

And damaging the ozone layer.

Dr. Pamela Gay: 

And yeah.

Fraser Cain:   

Yeah. And that’s the, and that’s another kind of direct thing that you’re getting. So, so you’re getting this again, direct damage to the ozone layer and you’ve got the rockets going up and you’ve got the, the material coming back down, damaging the ozone layer and you’ve got the additional.

And I think I can see why you’re like, it’s not so cut and dry. You can’t just say it’s going to be like carbon dioxide or even methane or even water vapor injected into the atmosphere. It’s complicated that you’ve got this stuff coming down and adding soot at layers where you wouldn’t necessarily expect it to absorb temperature, but then it’s going to be changing temperatures at other layers.

So it’s going to make the climate, the atmosphere stack more complicated.

Dr. Pamela Gay: 

There’s weird, weird effects. We’re still trying to figure out. So for instance, as you put more and more conductive molecules into the atmosphere, how is that going to affect things like Aurora and magnetic fields and things like that?

We’re figuring it out. It’s going to be affecting both light coming down and light going back out. How does that balance out?

And then we also have to remember that not everything burns up completely. And a lot of these spacecraft have on board fuels that allow them to adjust their altitude for however long they intend to be functioning. And so now there’s always that concern of, well, did that carry hydrazine?

Did that carry some poisonous component that’s going to make its way down? Or is it just something that has chunks that are… We like to bomb Australia.

It’s not on purpose. It just happens to be big and… They’re big, yeah.

Yeah, it…

Fraser Cain:   

Underfoot.

Dr. Pamela Gay: 

Catches things. Yeah, exactly. Exactly.

So between concern of remaining gases on board that are going to end up either on the ground or in the atmosphere, between now we’re putting new kinds of particulate materials that aren’t the pieces of rock that we’re used to burning up in the atmosphere, between not understanding how these particles are necessarily going to stay lofted, not fully understanding how they’re going to interact with each other to stay lofted in the planet’s magnetic field, there’s a whole lot of stuff we just don’t know.

And one of the things that always kind of sticks in the back of my mind is, in research on climate change, the biggest differences between what we’re seeing today and what was predicted in the early 2000s when we started talking about this with major papers coming out in around 2003, the mistakes we have made have been in lack of imagination about all the sources that we’re going to have for things producing greenhouse gases and lack of understanding all the atmospheric details.

Now, the one thing I can say is as we keep dumping completely empty boosters that previously contained liquid fuels, we are creating potential coral reefs. I’m a fan of potential coral reefs, but that’s the only good thing I’ve seen so far. And you know, the Navy already had it handled.

They were dumping old ships. It worked. We don’t necessarily need rockets too.

Fraser Cain:   

Yeah. Yep. So, I mean, what do you think can be done about this?

I mean, I think we should just be, we can guarantee that humanity’s interest in launching rockets will increase.

Dr. Pamela Gay: 

Yeah.

Fraser Cain:   

And that we will probably blow through what are wise limits in number of rockets to launch.

Dr. Pamela Gay: 

What I just don’t know right now is we live in a world where there are economic factors that are dominated by people trying to obtain so much wealth that it becomes power at the national, global level that they’re going to prioritize obtaining wealth over welfare of humanity.

Fraser Cain:   

I mean, I don’t sort of necessarily buy into that personally that, you know, everybody driving their cars all the time, everybody hopping on airplanes, everyone getting on cruise ships, everybody, everybody burning and contributing.

Dr. Pamela Gay: 

Yeah. So I hear what you’re saying, but the majority of the greenhouse gases and other materials that are infecting our atmosphere are produced by, I forget how many corporations it is, but it’s.

Fraser Cain:   

70 or something, 40, some small number. Yeah, of course.

Dr. Pamela Gay: 

So the majority of the impact is not coming from those airplanes. It is coming from industry. It’s coming from industry.

Fraser Cain:   

And so. Or the industry that makes the airplanes, right? Like the, I mean, there are externalities and I guess this is where I think this conversation always needs to end to, which is that there are externalities, that you can’t just launch a rocket and not think about what you’re doing to the environment, that there are costs and whether, whether the costs have to be paid today or the costs have to be paid in the future, somebody is going to have to pay the costs. And in general, if you’re organized, you minimize the cost that anybody’s ever gonna have to pay ever right from the beginning. You take this, you take these future costs very seriously.

This potential tragedy of the commons and that that there are actions that we can take both in the types of fuels people are proposing, soot-free rocket fuels. People are proposing ways of making satellites, you know, either dumping them in in so they hold together and don’t burn up in the atmosphere, right? Like there’s a lot of ideas from cradle to grave on what you can do for the entire rocket industry.

For me, my hope is that we switch to a space-based infrastructure. That we, that if we’re gonna need things in space, we build them out in space. They don’t come from Earth.

And then they don’t have to crash back down to Earth. They just have never, they were born off Earth, they stay off Earth. That, that who cares what’s, you know, sort of how much pollution they’re causing because it’s just out in space.

That would be my preference. And that we shift away. Then maybe there’s this future where we launch a couple of rockets a year of people going off into space and that none of the other infrastructure is required.

Everything just happens off off Earth. But, but until then, we need to figure out ways to minimize their footprint now for when we know that it’s going to, you know, ruin the commons in the future.

Dr. Pamela Gay: 

And, and this is where people who, like so many of you out there watching, who want to understand the peer-reviewed, published science behind conversations like we’re having today, need to make their voices heard. Because we’re seeing in, in so many nations around the world, with my own nation leading the charge it appears, that, that profit is dominating in the short term over the long-term taking care of our world to make sure that economies continue into the future. And we’re even hearing far too many discussions about, you don’t need to worry because the rupture is coming.

Fraser Cain:   

Right, yeah. So consider the externalities.

Dr. Pamela Gay: 

Yeah.

Fraser Cain:   

You know, when you are making proposals, consider the externalities. When you are government, when you’re writing laws, consider the externalities. Make sure that they are part of the process and that then people can make a better decision on what is the true cost of some technology once you consider the long-term ramifications of what it’s going to be doing to the environment.

Because it is a, it’s a shared space for all of us.

Dr. Pamela Gay: 

And there is no one answer. That’s the important thing to remember. It’s sort of like, I should never own an electric vehicle because what goes into building one is substantial and we drive maybe 5,000 miles a year.

So yeah, it’s the answer.

Fraser Cain:   

That’s a whole other conversation.

Dr. Pamela Gay: 

Yeah.

Fraser Cain:   

It’s about nine months of driving an electric car then balances out and then it’s all gravy between an ICE and an electric car. That’s another conversation for another show. All right.

Thanks, Pamela.

Dr. Pamela Gay: 

Thank you, Fraser. And thank you to all of the people out there who support us through Patreon. We are in the process of updating our levels and what we’re doing.

We’re adding a new That Takes Math Q&A show in which I am working out problems that we are unable to answer during our live recordings because that takes math. So if you would like access to the live recordings of that insanity and so much more, check us out on astronomycast.com slash Patreon. No, I said that wrong.

On patreon.com slash astronomycast. I need to make both links work.

Fraser Cain:   

We should make both work. Yeah, if you go to astronomycast, it takes you over to Patreon. Thanks, Pamela.

We’ll see you next week. Bye-bye. 

Live Show

This week, we look at the process behind rockets getting licensed to launch, and everyone around the pad getting notified to stay away as T-0 approaches. (Can you say “errant boat”?) We have a saying around here: “One does not simply book a return trip from a rocket launch.” That’s because they are an intensely complex chain of events that need to go right before it’s wise to let that rocket leave the launchpad. 

Show Notes

• Launch site & licensing
• Environmental reviews
• Safety corridors
• Mission specifics
• Weather rules
• Launch windows
• Countdown design
• Abort & FTS
• After launch

Transcript

Fraser Cain: 

Astronomy Cast, Episode 764, cleared for launch. Welcome to Astronomy Cast, our weekly facts-based journey through the cosmos, where we help you understand not only what we know, but how we know what we know. I’m Fraser Cain.

I’m the publisher of Universe Today. With me, as always, is Dr. Pamela Gay, a senior scientist for the Planetary Sciences Institute and the director of Cosmogloss. Hey Pamela, how are you doing?

Dr. Pamela Gay: 

I am doing well. I am team Lava Lamp. I have joined the cadre of websites that hide behind CloudFlare and won my battle with bots thanks to a little help from a giant organization.

And now I’m here to discuss the science. We’re recording on a Wednesday, and I appreciate everyone’s patience as I slayed my personal web server demons.

Fraser Cain: 

Yes. Yeah. Another vote for me for CloudFlare.

I hide Universe Today behind CloudFlare, and they cache 98% of the content that’s on Universe Today. Now it’s all HTML documents and images, but it’s incredible how much my web server just sits unused all the time, occasionally providing a page over to CloudFlare, and then CloudFlare is doing all the heavy lifting of generating that. And in fact, we have different policies.

You’re trying to use CloudFlare to stop all of the voracious AI scrapers that are tearing apart your site. I just let them all through. So you have that control.

In your case, you’re like, no, this is bringing my entire organization to its knees. And I’m like, I don’t care. Creative Commons 4.0, fill your boots, train away.

Dr. Pamela Gay: 

I would be fine if the servers didn’t keep falling over. So reconstructing the servers is in the plans, but I don’t have the time. So right now, CloudFlare.

Fraser Cain: 

Yeah. And when I used to be running WordPress, when I used to be running something that was PHP heavy, I had to do that same thing. Now my web server is only HTML documents and images and is incapable of running scripts.

And so it is incapable of sort of having scripts run a mock. So yeah, I don’t really care. But the point is, man, CloudFlare is a pretty great way to protect your content.

This is not an ad. They are not paying us. We are just literally both.

[Speaker 3]

They could.

Fraser Cain: 

They could. Yeah. CloudFlare, if you want to put an ad on an astronomy cast, now’s your chance.

We have a saying around here. One does not simply book a return trip from a rocket launch. That’s because they are an intensely complex chain of events that need to go right before it’s wise to let that rocket leave the launch pad.

All right, Pamela, give me your most hilarious, uh, the rocket didn’t launch when it was supposed to story and, and your trials and tribulations of having to deal with that.

Dr. Pamela Gay: 

Oh man. Um, so I think the most delightful was the launch of the, I think it was the LADEE mission on a Delta, Delta some number, I don’t remember the number. I was down Cape Canaveral.

I was part of one of the NASA social events as one of the talking heads and, uh, the launch was supposed to be stupid early in the morning, really early in the morning. And so they get us out to this adorable little boat dock area that NASA owns and, and it’s so early and we’re watching the sun come up. I hate mornings.

I am, as we’ve determined, three coffees and a trench coat and we’re all there and we’re all like, okay, just launch, we’re going to go back to bed. And it did not launch. And so we’re all out there and we’re like, are they going to reset?

And they reset, they did reset. And, and then manatees were discovered. And so you have all these people waiting for a rocket launch that are now obsessing, is that a crocodile?

Wait, that’s a manatee. There are more than one manatees. And then somebody figured out that if you turn on the freshwater tap, that’s meant for boats, the manatees will come over and they have these like mouths that are just adorable and horrifying simultaneously.

And so there was this like swarm of manatees all like knocking each other out of alignment to drink the fresh water from the freshwater tap. And so all of these people that have traveled, who knows how many miles and plane trips and hours in a car to see a rocket launch are now completely obsessed with the manatees drinking the water.

Fraser Cain: 

That’s amazing.

Dr. Pamela Gay: 

And, and then the Delta went up, but I had never seen a Delta go up before and was not prepared for the fact that it just kind of sits there for a hot second, completely surrounding itself in clouds. And I’m there as the talking head. I’m like, oh, no, did it just blow up?

Am I going to have to explain that it just blew up? Oh, God, I’m going to have to. This is very rapid fire going through my brain.

And then the tip of the rocket starts to come out of the clouds. I’m like, OK, we’re good. We’re good.

It was a good day. Manatees and no explaining rocket explosions. So, so that that was my story.

Fraser Cain: 

Yeah, mine is that I went to take my father, who is a professional photographer, to watch the penultimate launch of the space shuttle. And so we went down to Cape Canaveral and got set up to photograph and and we did all the various tours and go out and you see the shuttle and and all of that. And then it was set to launch and there was a launch delay.

And we’re like, OK. And they said, no, the launch delay is like five days. And so we had a week in Florida before we had to go back.

[Speaker 3]

Yeah.

Fraser Cain: 

And so we went down to Miami, had a good time down checking out Miami. And then we came back to Cape Canaveral. The day was supposed to launch.

It was scrubbed again. And so we had to fly home and not watch the space shuttle launch.

Dr. Pamela Gay: 

Oh, no. I had the opposite experience in January with Blue Origin. I went to Florida.

I booked two straight weeks. I have a timeshare literally so that I can cover rocket launches. It’s just easier this way.

And I was there also for podcast movement conference. And the day I arrived was the day that Firefly launched. And and so I’m like dragging my sorry self after a 5 a.m. flight all the way from Orlando to the Space Coast. And I’m like, it’s there’s no way it’s launching. Totally launched, totally launched at 2 a.m. And then I it was cold. It was like freezing temperatures, frost, cold in Florida.

And so I drive all the way back to Orlando where my hotel is. And the next day was supposed to be Blue Origin. Blue Origin had already been delayed several times at this point.

And the email I get is we think we’re go for tonight. Here’s the location. We are on the roof of this hotel.

And I’m like, it’s 20 degrees. There is no way they’re launching tonight. I am so cold.

I am so tired. I am staying put. And they did not launch.

Fraser Cain: 

Right.

Dr. Pamela Gay: 

And and then the next night, still so cold. And they’re like, we do not have a place for media tonight. And I’m like, I’m a woman traveling alone.

And you are launching in the middle of the night. And I emailed them this. And I’m like, where should I go?

And I will be safe. And they’re recommending like parks after dark. And I’m like, no, no.

Fraser Cain: 

Sounds like a good idea.

Dr. Pamela Gay: 

Yeah.

Fraser Cain: 

And I’ve wandered through crocodile or alligator infested bogs.

Dr. Pamela Gay: 

Yeah. And it was definitely a do you trust the bear or the human kind of a concern going on? And and so I was like, I’m staying in my hotel room.

I’m going to be warm on the Internet. And of course, they ended up launching the night. They didn’t have a place for media.

And so I was in Orlando, in my hotel room, in bed, in pajamas, watching launch, talking in chat on Discord.

Fraser Cain: 

Is that the rocket I’m here to watch?

Dr. Pamela Gay: 

Yeah. Yeah. So I I currently Blue Origins second launch is slated for while I’m at an event, I’m going to be at Magikon in Atlanta discussing the science of Magic the Gathering cards.

So I’m kind of hoping they’re delayed and I’ll try again in November if they’re delayed. I’m evil. I shouldn’t wish delays on rockets.

I am wishing a delay on this rocket.

Fraser Cain: 

All right. So we’re going to continue this conversation in our normal astronomy cast style, but I believe we just described many of the various trials and tribulations that rockets go through to be able to actually launch. All right.

So let’s talk about the sort of what it takes to actually light this candle.

Dr. Pamela Gay: 

All right. So so it all starts with someone had to get the spaceport approved and then someone had to approve the rocket for the spaceport. And what’s really cool is right now we can follow along pretty much in real time as SpaceX goes through all the paperwork to get certified to launch their starship from Cape Canaveral and Kennedy Space Flight Center.

So there’s two different pads that they’re looking at. One of the pads is much further along in the approval process, and they’re having to figure out everything from where are the locations that if you’re standing there, you experience 100 decibels of sound, 80 decibels of sound, 60 decibels of sound. And so that goes into the where do humans need to not be.

They are working to figure out if the sucker blows up, where do you not need to be so that you survive? And and so all of these things end up going into maps. They also end up having to figure out where are all of the sonic booms going to be?

What is this going to disrupt? And the other thing they have to figure out is what is the clearance zone around your spacecraft? And now they have to figure it out both for launch and return in which boats can’t be located because if you blow up, you’ll sink them.

And boats can’t be located because the shock wave will do really bad things to anyone on board the boat. 100 decibels is bad. Do not experience 100 decibels.

And they also have to figure out where aircraft should not be attempting to fly, because aircraft versus rocket is called a missile. So so there are so many maps that have to be done. You have to figure out the the error in your navigation, which is getting to be a smaller and smaller number.

You have to figure out in order to get to all the different orbits that you want to service with your rocket. What is the span of places that are going to have to become no boat and no fly zones? And and a lot of planning that I hadn’t really thought through in terms of if you’re going into a polar orbit, your trajectory is totally different than if you’re going into an equatorial orbit.

And so you have to have different notams, which are either notices to aviation or notices to maritime people. And there is more paperwork than you can file with less than a committee of humans.

Fraser Cain: 

Yeah, yeah. And and so that is you choosing, as you say, getting your site chosen. That is you making sure that the rocket class that you are attempting to launch from this facility isn’t going to tear apart the fabric of reality at a fundamental level, that this rocket is is the right fit for the right launch site.

And there are a bunch of these launch sites. So you mentioned the Kennedy Space Center.

[Speaker 3]

Yeah.

Fraser Cain: 

But there’s Wallops. There’s Vandenberg, Vandenberg and and these. And so Wallops is a good example where they don’t.

You wouldn’t see super heavy taking off from Wallops. Too many humans. Too many humans.

Yeah, yeah, sure. Right. Maybe.

Yeah. So you’re going to see these smaller rockets depending on the on the facility and depending on what the class of the mission is and how far away it is from where they want to be able to bring their stuff. So, OK, so you’ve you’ve kind of gone through this process.

You’ve cleared the launch site. You’ve gotten approval that you’re able to launch this rocket. Then comes the actual specific mission that you’re planning, and then it’s an entirely other approval process.

Dr. Pamela Gay: 

Yeah. And there was one thing that we didn’t bring up, which is the turtles. All of these launch facilities that you mentioned are on the ocean.

They’re near beaches. And and so part of the process of getting launch approval is actually in in Vandenberg. SpaceX had to go out and monitor how launches affected the the nesting seabirds in the wildlife preserves nearby to make sure that launches and this is also a big sea lion issue, making sure that their launches don’t disrupt the breeding cycle of these animals.

So you have people going out and counting and watching the behavior of all of these animals along the beaches. And there’s actually been problems with when Starship blew up, it scattered pieces all over a Mexican beach where baby sea turtles were attempting to go from beach to ocean. And we’re encountering chunks of Starship that got in their way.

So so they also have to do wildlife assessments. And in reading through the the Environmental Protection Agency report on launching Starship from Cape Canaveral, they were like, it’s not going to be a bigger impact than what we’re already doing. And they have to figure all of this stuff out.

And most of these locations are wildlife preserves, because that’s a really good way to keep humans from building houses there. And you don’t want to build houses near a launch pad. Rockets make bad neighbors.

Watch the last episode of EVSN to hear about that one.

Fraser Cain: 

Yeah, that’s interesting that that the the place where you want to build a rocket is also the place where you want to protect nature.

Dr. Pamela Gay: 

Exactly, exactly. Visiting the Cape, we’ve both seen the big eagles nest that.

Fraser Cain: 

Yes. And I’ve seen that exact manatee dock. I know exactly what you’re talking about.

Yeah.

Dr. Pamela Gay: 

Yeah. Awesome.

Fraser Cain: 

Yep. So but but with back to my original question, you know, the mission. So so depending on what the what the the spacecraft is going to have solid rocket boosters, is it going to have a bigger upper stage?

It can have a kick stage. What is the satellite payload is supposed to do? These all have to be reviewed as part of the actual launch.

And there’s a state there’s every time you try to do something new, you have to go through this process again.

Dr. Pamela Gay: 

And the doing something new can include changing your control room, for instance. So so when you have a launch license, the launch license is as specific as we are going to be controlling communications from this room in this building. We are going to be using this explosive device to blow it up if we have to.

We are going to be controlling everything with this software. It goes all the way through the entire process. And every stage has to be approved, which means that when we see these new commercial space companies go from the tiny buildings of we’re a baby company, this is all we’ve got to massive.

OK, we’re doing OK. We can build a bigger building because we have more humans. They have to get recertified for each change in control room.

And SpaceX actually has has been fined for filing the paperwork, but not waiting for it to get approved and moving their control room early. It’s a complicated process that was designed to be the kind of thing that federal contractors are just used to. Military is just used to.

And it’s been an adventure to watch all of the new commercial space people be like, but what do you mean paperwork? And it’s to protect everyone on these shared facilities.

Fraser Cain: 

Yeah, I mean, it’s hard to imagine something that is both sort of important for the economy, that is also as dangerous as a rocket, which is a giant tube filled with explosives that is fire at thousands of kilometers per hour. Yeah, I wouldn’t just, you know, out away over terrain, right? Like there’s so many things that can go wrong and we have seen them go wrong.

All right. So you’ve got your launch site. You’ve got your your rocket is matched to your launch site.

You have gone through the process to approve your specific mission that you’re going to be doing.

[Speaker 3]

Yeah.

Fraser Cain: 

Now you set a launch date and now there’s still a range of things that will challenge and complicate your ability to launch this actual rocket.

Dr. Pamela Gay: 

Yeah. So so the errant boat is my favorite. I just have to say, if you’re going to have a reason to not launch, the errant boat brings me joy because there have been cases of like rogue kayaker who got too close and stopped the launch from happening.

And and the they really put a lot of effort into making sure these are safe things. And so they define both a launch window, which is both the window that gets you to space on the orbit that you want. And also the we’re going to launch within this window.

And boaters were sorry you can’t go there. Then flights were sorry you can’t go there then. And and there’s a lot of times when we have a rocket that it really doesn’t matter when you launch the orbit.

It just doesn’t care. There’s also instantaneous launches, which are really easy on everybody, because if you don’t launch that second, you don’t get to where you need to be.

Fraser Cain: 

Right. Don’t wait till tomorrow.

Dr. Pamela Gay: 

But but all these other things that have launch windows that can be both because of your orbit and also because they don’t want to cut off flight for the entire day over your region.

Fraser Cain: 

And and it gets super complicated when you have these various technical challenges. There’s a fuel leak. There’s a lack of pressure in one of the lines.

And you you realize you’re going to have to to not scrub the launch. You have to push the launch back. Well, that means that all the people that are enforcing the the downrange boat closure have to then continue enforcing that.

And it can go on for hours and hours and hours and hours. And it just gets you know, after a while, you’re herding cats. People are are are moving through the area.

Crew ships need to have to go up and down. Yeah, there’s tons and tons of boats that are normally making this journey through these waters. And you’re literally closing down the waters for hours and hours and hours, trying to get all of these problems stamped out before you can actually make the launch happen.

The other big thing is weather.

Dr. Pamela Gay: 

So one thing I just want to add, though, is is the no boats. The no flights is something that’s impacting folks that are like not part of the aerospace industry. The other thing that happens is they have to clear out the surrounding launch pads and how many of the facilities down at the Cape along the Space Coast have to be emptied out depends on how big a rocket you’re launching.

And so they’re estimating that with Starship for the 76 launches a year, the surrounding pads that are owned by ULA, NASA and a blue origin, blue origin are going to be facing as many as 400 leave your site periods per year. Wow. Because you have to empty out.

Also, when you’re doing a test firing, the static firing tests are also dangerous, as as we found out back in June with Starship.

Fraser Cain: 

Yeah.

Dr. Pamela Gay: 

So so this also has commercial implications on your competitors, which is fascinating. But but weather weather does not care what company you are. It does not care if you’re private or military.

Those thunderheads are going to get you no matter what. And so they’re looking at a variety of different things that vary from rocket to rocket. And this is the cool thing.

Some rockets are just like I shall go through the clouds and nothing shall stop me. The Russians, it’s like nothing stops a Soyuz launch. They’re just going to go driving rain.

Sure. Why not? Down down at the Cape, the things that you frequently hear are top level winds.

So this is as you’re going up, you don’t want the winds to be so fast that you’re worried about what chaos they’re going to add to your trajectory. And that’s exactly what it is. These winds are a force that changes your course.

And can your rocket stay on the course? It needs to be in the face of these high level winds. The other thing you have to worry about is lightning.

They have lightning rods around all of the launch pads. But those don’t help when you’re flying through the atmosphere. And the rockets should be fine against lightning.

But no one wants to find out. Then there’s also visibility issues. They need to be able to see what’s going on at a certain degree.

And exactly which combination of where does the ceiling of the clouds need to be? What does the wind need to be? How far away does the lightning need to be?

Is on a per spaceport, per launch vehicle kind of basis.

Fraser Cain: 

And it’s even sort of per phase. So like right now, SpaceX is trying to test out Starship and they’re trying to find out, you know, what are the limitations of the super heavy booster? What kind of angles can they bring it back at?

How many engines can they lose and still be able to make a safe capture and so on and so forth? And and also they want to be able to watch the entire launch and see every single stage go off. Watch as as the adapter breaks off between super heavy and Starship.

Watch as Starship lights its engines. Watch as, you know, as it’s interacting and see what’s happening with the with the atmosphere. And so if you do have like a lot of fog or a low cloud deck, things like that, then you lose sight of your rocket and it makes it a lot harder.

And so for them, it’s worth it to delay the launch, push back the launch, get those clear skies, get the wind conditions that are within the range that they need to be able to to clear that for launch.

Dr. Pamela Gay: 

And they’re using drones which which have their own flight conditions. And the other thing that I think we need to remember is part of the you have to approve everything is as soon as SpaceX started doing the amazing videos with their Falcon nine that allowed you to see the entire process from onboard cameras. Everyone was like, NASA needs to add onboard cameras.

And then was like, why isn’t NASA adding onboard cameras? Because that requires updating your launch license.

Fraser Cain: 

Right.

Dr. Pamela Gay: 

And so there’s paperwork even for doing things like adding a camera to your rocket and changing how it’s configured. And that has to be space hardened. And and and so it takes time for ideas to propagate when you have an existing rocket that already has its launch licenses.

Fraser Cain: 

Yeah. Yeah. So now we’ve got, you know, we’ve worked through the the weather conditions, the launch conditions.

And there are going to be various technical issues that might come up with the rocket itself. But all of that has been cleared. And so as we sort of say everything is is go for launch and we start to reach sort of near the end of the of the countdown.

Dr. Pamela Gay: 

Yeah.

Fraser Cain: 

We often see this pause.

Dr. Pamela Gay: 

Yeah.

Fraser Cain: 

Where they, you know, they put in a go pause. Well, they like they’re like a planned hold.

Dr. Pamela Gay: 

Yeah. Yeah.

Fraser Cain: 

And so what’s going on there? Why are they doing this right at the end before they launch?

Dr. Pamela Gay: 

So countdown clocks are designed as something that gives you a checklist of this happens at this point, this happens at this point, this happens at this point. And there’s different philosophies on how you design your countdown. And it’s fun to see how this works out differently, especially where like I, you and I grew up watching the space shuttle that had a whole variety of planned holds in its countdown.

And those planned holds were people did things that they thought would probably take five to 10 minutes or maybe 20 minutes. So they’d go into a planned hold and say, we expect this planned hold to last. And they’d say how long they expected it to last.

But it didn’t necessarily last that long. So the planned hold allows them to have flex in their countdown for launches that have a window versus an instantaneous launch. And they often run checklists.

Fraser Cain: 

Yeah. And you can see it like if you got humans that are climbing aboard your spaceship and doing human things, then there’s a support. Then you’re still following the larger timeline of your countdown.

But one of those things is getting all of your astronauts to climb inside the space shuttle and and hook up all their umbilicals and and make sure everything is right. And and you think it’s going to take you X amount of time, but it actually takes you Y amount of time. And so that will push it.

But with the satellite launches and stuff, these planned holds can be very quick. Like sometimes just a few seconds, 30 seconds or something they’ve got to do. They’ve got to make sure it has to be done at that moment.

And you’ll see that that planned hold.

Dr. Pamela Gay: 

And human versus satellite. You have two things that that become suddenly very different. First of all, the loading of the humans and the closing of the door and the ceiling of the door that can’t be done ahead of time.

That has to be done that day. You’re not locking the humans in five days in advance, like with the satellite.

Fraser Cain: 

Yeah, just stay in there and launch there for a while. Yeah.

Dr. Pamela Gay: 

But but the other issue is with with humans, you have all of the abort locations. So abort to here, abort to there. In case of issue, we saw this, I want to say eight years ago where they had to do an abort of a Soyuz and then they had to go figure out where in the forest the Soyuz went.

And and so you have to do the check of not just the weather at the launch facility, but the weather at all of your abort to locations. So you have two different things that get added in with human beings. OK, I’m done.

Move on to the next topic. Sorry.

Fraser Cain: 

No problem. So now, you know, we get down to zero. The it’s we go for launch.

They start the the rocket begins. But there’s still one phase that may stop this rocket from continuing on to orbit. And that is if something catastrophically bad happens to the rocket and not like it tears itself apart, but there’s something wrong and they need to still abort the launch.

Dr. Pamela Gay: 

Yeah. So luckily, we don’t see this too often, but there’s been some amazing examples from new commercial spaces. They’re developing new rockets.

So I can’t tell you how many times we’ve seen a rocket just start to clear the launch pad and then fails. My favorite failure was and this happened not in the final few seconds. There was a rocket recently that decided to just like fling its satellite fairings.

So sitting on the launch pad and suddenly you have naked satellite. It was glorious.

Fraser Cain: 

It was still take off.

Dr. Pamela Gay: 

No, no. They’re like, oh, no, we can’t. We no longer have fairings.

Fraser Cain: 

But I mean, no, we know that rocket is going to make it without fairings. Yeah.

Dr. Pamela Gay: 

Just the idea that your rocket suddenly goes spring. No more fairings on the launch pad. It yeah, I love it.

We’ve we’ve seen launches where it goes up and it turns around and you detonate it before it can destroy your launch pad.

Fraser Cain: 

And that’s the key is that detonation, that there needs to be a way to explode your rocket if it’s doing something catastrophic. It’s going in exactly the wrong direction. If it veers left and heads toward a city, you need to be able to detonate that rocket and stop it from going any further.

Dr. Pamela Gay: 

Yeah. And and I go check out some of the videos there. There are rapid unplanned disassembly videos. There is lithographic breaking videos.

New Commercial Space is providing us modern 4K video of things that last happened in the 60s, and I am here for the innovation and occasional mistakes.

Fraser Cain: 

Yeah. Yeah. So that is the sort of chain of events you have to get through.

And it’s kind of amazing how many of these little steps, and I’m sure someone who actually works in the rocket industry is like, you have no idea how many of these little things we have to deal with step by step by step. This is gigantic chain of events where it can go wrong at every step of the way. And yet, incredibly, rockets launch and they go to space and it works.

Dr. Pamela Gay: 

And it would be a completely different conversation to talk about everything that goes into docking. We saw earlier this week, Cygnus rocket, Cygnus Extra Large, that was designed to be able to boost the International Space Station had a rocket issue. And I haven’t checked to see if that’s been fixed yet, but they had to abort their docking with the International Space Station because weren’t going to be in the right place at the right time.

And this is a new capsule that they’re working with.

Fraser Cain: 

All right. Well, maybe that’s a future episode. Thanks, Pamela.

Dr. Pamela Gay: 

Thank you, Fraser. And I’m going to record names after the fact. Go join us on Patreon.

We are adding all sorts of new things. I am still figuring this out, which is why we are not recording the names right now. And Fraser and I are moving everything we do one step at a time into this happy place that doesn’t have AI recommending what we do and create.

And check out if you’re listening to this podcast and you want to hear more about what I just said. We had a magnificent rant on the live recording on YouTube about all the things YouTube is doing to us. So, yeah.

Fraser Cain: 

Thanks, everyone. And we will see you next week.

Dr. Pamela Gay: 

See you next week. Bye-bye.

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