Astronomy

Both a special diet that excludes “FODMAP” compounds and a low-carb high-fibre diet were effective

Rocket Lab has put a recovered Electron first stage back into its production line, a big step toward the company's first-ever rocket reflight.

Back in the 1960s and 1970s, Apollo astronauts set up a collection of lunar seismometers to detect possible Moon quakes. These instruments monitored lunar activity for eight years and gave planetary scientists an indirect glimpse into the Moon’s interior. Now, researchers are developing new methods for lunar quake detection techniques and technologies. If all goes well, the Artemis astronauts will deploy them when they return to the Moon.

Fiber optic cable is the heart of a seismology network to be deployed on the Moon by future Artemis astronauts.

The new approach, called distributed acoustic sensing (DAS), is the brainchild of CalTech geophysics professor Zhongwen Zhan. It sends laser beams through a fiber optic cable buried just below the surface. Instruments at either end measure how the laser light changes during the shake-induced tremors. Basically Zhan’s plan turns the cable into a sequence of hundreds of individual seismometers. That gives precise information about the strength and timing of the tremors. Amazingly, a 100-kilometer fiber optic cable would function as the equivalent of 10,000 seismometers. This cuts down on the number of individual seismic instruments astronauts would have to deploy. It probably also affords some cost savings as well.

A seismometer station deployed on the Moon during the Apollo 15 mission. Courtesy NASA. DAS and Apollo on the Moon

Compare DAS the Apollo mission seismometer data and it becomes obvious very quickly that DAS is a vast improvement. In the Apollo days, the small collection of instruments left behind on the Moon provided information that was “noisy”. Essentially, when the seismic waves traveled through different parts of the lunar structure, they got scattered. This was particularly true when they encountered the dusty surface layer. The “noise” basically muddied up the signals.

The layout for the Apollo Lunar Seismic Profiling Experiment for the Apollo 17 mission. Courtesy Nunn, et al. What DAS Does to Detect Quakes on the Moon

The DAS system stations laser emitters and data collectors at each end of a fiber optic cable. This allows for multiple widely spaced installations that measure light as it transits the network. The cable consists of glass strands, and each strand contains tiny imperfections. That sounds bad, but each imperfection provides a useful “waypoint” that reflects a little bit of the light back to the source. That information gets recorded as part of a larger data set. Setting up such a system of telecommunications cables over a large area provides millions of waypoints that scientists can use to measure seismic movements on Earth.

A recent study led by CalTech postdoctoral researcher Qiushi Zhai deployed this type of DAS-enabled fiber optic cable system in Antarctica. The conditions mimic some of the environmental challenges of a lunar deployment—it’s freezing cold, very dry, and far removed from human activities. The sensors measured the small movements of caused by ice cracking and moving around. Those types of signals are perfect analogs to lunar quakes.

Aerial view of Antarctica. A prototype of the lunar DAS system for the Artemis missions to the Moon detected tiny tremors from ice movements here. Photo credit: L. McFadden 2008 Measuring a Lunar Quake Using DAS

Since DAS works well measuring tiny tremors induced by ice, it seems like the perfect “next step” in doing lunar seismology. On the Moon, the fiber optic cable would be buried (just as cables are on Earth) a few centimeters below the level of the regolith. It will sit there waiting for the next quake, which probably won’t take long, since the Moon seems to quiver frequently. When one strikes, its seismic waves will move through the ground from the source. They’ll wiggle the cable. That will affect the light-travel path inside. The actions of light hitting thousands of imperfections inside the cable will provide lunar geologists with high-precision data about moonquakes. That includes their origins, travel time, and other aspects of the wave that will help them understand more about the lunar structure they travel through.

The distributed nature of the seismic network will have a big advantage over the Apollo-style individual seismometers used in the past. And, there are other reasons to use DAS, according to Zhai. “Another advantage of using DAS on the Moon is that a fiber optic cable is physically quite resilient to the harsh lunar environment: high radiation, extreme temperatures, and heavy dust,” Zhai said.

Moon Structure and DAS

Zhai is the first author of a paper describing the DAS system, which should allow scientists to detect close to 100 percent of Moon tremors. The paper offers insight into the advantages that DAS offers. In particular, such an array stretched across large areas of the Moon should provide much higher-quality data about even the smallest tremors that shake the surface.

Since the Moon is not tectonically active, its quakes don’t occur from the same causes as they do on Earth. Some happen during the sunset/sunrise period when temperature changes affect the surface. Others happen thanks to Earth’s pull on the Moon, and still others occur because the Moon is still cooling and contracting. Zhai’s paper suggests that DAS could detect about 15 moonquakes per day, and perhaps help better characterize the thermal moonquakes that happen at sunrise/sunset and the deeper ones that occur during perigee and apogee portions of its orbit, and those intrinsic to the Moon’s contraction. In addition, impacts on the Moon also generate quakes. Information about all these events should give planetary scientists a big leg up on understanding more about the lunar interior structure.

The deployment of DAS and other science experiments will be part of the surface operations of the Artemis missions. It will be part of one of the proposed seven-month stays for astronaut teams. Although there is no specific planned date for seismometer deployment, it’s likely to take place no sooner than the mid-2030s. That’s after the planned missions to build shelters, deploy power stations, and other activities to create the lunar bases.

For More Information

A New Type of Seismic Sensor to Detect Moonquakes
Assessing the feasibility of Distributed Acoustic Sensing (DAS) for Moonquake Detection
Lunar Seismology: A Data and Instrumentation Review

The post Artemis Astronauts Will Deploy New Seismometers on the Moon appeared first on Universe Today.

The Transformers are returning to cinemas in 2024 with their first animated movie in nearly 40 years. This is the beginning of Cybertron's end.

The dwarf planet Ceres has some permanently dark craters that hold ice. Astronomers thought the ice was ancient when they were discovered, like in the moon’s permanently shadowed regions. But something was puzzling.

Why did some of these shadowed craters hold ice while others did not?

Ceres was first discovered in 1801 and was considered a planet. Later, it was thought to be the first asteroid ever discovered, since it’s in the main asteroid belt. Since then, our expanding knowledge has changed its definition: we now know it as a dwarf planet.

Even though it was discovered over 200 years ago, it’s only in the last couple of decades that we’ve gotten good looks at its surface features. NASA’s Dawn mission is responsible for most of our knowledge of Ceres’ surface, and it found what appeared to be ice in permanently shadowed regions (PSRs.)

New research shows that these PSRs are not actually permanent and that the ice they hold is not ancient. Instead, it’s only a few thousand years old.

The new research is titled “History of Ceres’s Cold Traps Based on Refined Shape Models,” published in The Planetary Science Journal. The lead author is Norbert Schorghofer, a senior scientist at the Planetary Science Institute.

“The results suggest all of these ice deposits must have accumulated within the last 6,000 years or less.”

Norbert Schorghofer, senior scientist, Planetary Science Institute.

Dawn captured its first images of Ceres while approaching the dwarf planet in January 2015. At that time, it was close enough to capture images as good as Hubble’s. Those images showed craters and a high-albedo site on the surface. Once captured by Ceres, Dawn followed a polar orbit with decreasing altitude. It eventually reached 375 km (233 mi) above the surface, allowing it to see the poles and surface in greater detail.

“For Ceres, the story started in 2016, when the Dawn spacecraft, which orbited around Ceres at the time, glimpsed into these permanently dark craters and saw bright ice deposits in some of them,” Schorghofer said. “The discovery back in 2016 posed a riddle: Many craters in the polar regions of Ceres remain shadowed all year – which on Ceres lasts 4.6 Earth years – and therefore remain frigidly cold, but only a few of them harbor ice deposits.”

As scientists continued to study Ceres, they made another discovery: its massive Solar System neighbours make it wobble.

“Soon, another discovery provided a clue why: The rotation axis of Ceres oscillates back and forth every 24,000 years due to tides from the Sun and Jupiter. When the axis tilt is high and the seasons strong, only a few craters remain shadowed all year, and these are the craters that contain bright ice deposits,” said lead author Schorghofer.

This figure from the research shows how Ceres’ obliquity has changed over the last 25,000 years. As the obliquity varies, sunlight reaches some crater floors that were thought to be PSRs. Image Credit: Schorghofer et al. 2023.

Researchers constructed digital elevation maps (DEMs) of the craters to uncover these facts. They wanted to find out how large and deep the shadows in the craters were, not just now but thousands of years ago. But that’s difficult to do since portions of these craters were in deep shadow when Dawn visited. That made it difficult to see how deep the craters were.

Robert Gaskell, also from the Planetary Science Institute, took on the task. He developed a new technique to create more accurate maps of the craters with data from Dawn’s sensitive Framing Cameras, contributed to the mission by Germany. With improved accuracy, these maps of the crater floors could be used in ray tracing to show sunlight penetrated the shadows as Ceres wobbled over thousands of years.

This figure from the study shows some of the DEMs the researchers developed for craters on Ceres. White regions represent sunlit areas, while the coloured contours represent PSRs for different axial tilts. Image Credit: Schorghofer et al. 2023.

The DEMs in the above image show that at 20 degrees obliquity, none of the craters are in permanent shadow. That means none of them have truly permanent PSRs. “A PSR starts to emerge in Bilwis crater at about 18°, and they emerge at lower obliquities at the other six study sites. This implies that the ice deposits are remarkably young,” the researchers write in their paper.

This figure from the research shows PSRs in the north-polar region of Ceres. The colour scale shows how oblique each crater is. The research shows that 14,000 years ago, none of these were PSRs, and the ice they hold now is only 6,000 years old. Image Credit: Schorghofer et al. 2023.

About 14,000 years ago, Ceres reached its maximum axial tilt. At that time, no craters were PSRs. Any ice in these craters would’ve been sublimated into space. “That leaves only one plausible explanation: The ice deposits must have formed more recently than that. The results suggest all of these ice deposits must have accumulated within the last 6,000 years or less. Considering that Ceres is well over 4 billion years old, that is a remarkably young age,” Schorghofer said.

So, where did the ice come from?

There must be some source if the ice is young and keeps reforming during maximum obliquity. The only plausible one is Ceres itself.

“Ceres is an ice-rich object, but almost none of this ice is exposed on the surface. The aforementioned polar craters and a few small patches outside the polar regions are the only ice exposures. However, ice is ubiquitous at shallow depths – as discovered by PSI scientist Tom Prettyman and his team back in 2017 – so even a small dry impactor could vaporize some of that ice.” Schorghofer said. “A fragment of an asteroid may have collided with Ceres about 6,000 years ago, which created a temporary water atmosphere. Once a water atmosphere is generated, ice would condense in the cold polar craters, forming the bright deposits that we still see today. Alternatively, the ice deposits could have formed by avalanches of ice-rich material. This ice would then survive in only the cold shadowed craters. Either way, these events were very recent on an astronomical time scale.”

There are other potential sources of water ice. Ceres has a very thin, transient water atmosphere. The water could come from cryovolcanic processes and then be trapped and frozen in shadowed regions.

Ceres also has a single cryovolcano: Ahuna Mons. It’s at least a couple hundred million years old and long dormant. There are dozens of other dormant potential cryovolcanoes, too. But these likely aren’t the water source.

There’s ample water ice at shallow levels in Ceres. If the dwarf planet erodes over time, mass-wasting could expose and release water that freezes in the craters. “The few ice deposits that have been detected spectroscopically outside the polar regions are indeed often associated with landslides, and the sunlit portion of the ice deposit in Zatik crater is best explained by a recent mass wasting event,” the authors explain.

Ceres has been through a lot. As an ancient protoplanet that’s survived to this day, it holds important clues to the Solar System. Though its craters don’t hold ancient ice like once thought, deeper study is revealing the dwarf planet’s true nature.

“The ice deposits in the Cerean PSRs indicate an active water cycle; ice is either repeatedly captured and lost or frequently exposed, or both,” the authors conclude.

The post Ice Deposits on Ceres Might Only Be a Few Thousand Years Old appeared first on Universe Today.

CMSA said Shenzhou 18 will be launched at an appropriate time in the near future. However, airspace closure notices indicate launch is currently set for around 9:00 a.m. EDT on April 25 (1300 GMT, or 9:00 p.m. Beijing time).

Cocaine and morphine hijacked neural responses in the brains of mice, which resulted in them consuming less food and water

Cocaine and morphine hijacked neural responses in the brains of mice, which resulted in them consuming less food and water

Millions of viewers were wowed by last week’s total solar eclipse. Now, we get to see the eclipse from another angle: space.

The post See Amazing Views of the April 8th Total Solar Eclipse from Space appeared first on Sky & Telescope.

SpaceX launched its 40th mission of 2024 this evening (April 18), sending yet another batch of the company's Starlink internet satellites skyward.

Cosmic rays are high-energy particles accelerated to extreme velocities approaching the speed of light. It takes an extremely powerful event to send these bits of matter blazing through the Universe. Astronomers theorize that cosmic rays are ejected by supernova explosions that mark the death of supergiant stars. But recent data collected by the Fermi Gamma-ray space telescope casts doubt on this production method for cosmic rays, and has astronomers digging for an explanation.

It’s not easy to tell where a cosmic ray comes from. Most cosmic rays are hydrogen nuclei, others are protons, or free-flying electrons. These are charged particles, meaning that every time they come across other matter in the Universe with a magnetic field, they change course, causing them to zig-zag through space.

The direction a cosmic ray comes from when it hits Earth, then, is not likely the direction it started in.

But there are ways to indirectly track down their origin. One of the more promising methods is by observing gamma rays (which do travel in straight lines, thankfully).

When cosmic rays bump into other bits of matter, they produce gamma rays. So when a supernova goes off and sends cosmic rays out into the Universe, it should also send a gamma-ray signal letting us know it’s happening.

That’s the theory, anyway.

But the evidence hasn’t matched expectations. Studies of old, distant supernovas show some gamma ray production occurring, but not as much as predicted. Astronomers explained away the missing radiation as a result of the supernovas’ age and distance. But in 2023, the Fermi telescope captured a bright new supernova occurring nearby. Named SN 2023ixf, the supernova went off just 22 million light-years away in a galaxy called Messier 101 (better known as the ‘Pinwheel Galaxy’). And yet again, gamma rays were conspicuously absent.

NASA Goddard.

“Astrophysicists previously estimated that supernovae convert about 10% of their total energy into cosmic ray acceleration,” said Guillem Martí-Devesa, University of Trieste. “But we have never observed this process directly. With the new observations of SN 2023ixf, our calculations result in an energy conversion as low as 1% within a few days after the explosion. This doesn’t rule out supernovae as cosmic ray factories, but it does mean we have more to learn about their production.”

So where is all the missing gamma radiation?

It’s possible that interstellar material around the exploding star could have blocked gamma rays from reaching the Fermi telescope. But it might also mean that astronomers need to look for alternative explanations for the production of cosmic rays.

Nobody likes a good mystery better than astronomers, and digging into the missing gamma radiation could eventually tell us a whole lot more about cosmic rays and where they come from.

Astronomers plan to study SN 2023ixf in other wavelengths to improve their models of the event, and will of course keep an eye out for the next big supernova, in an effort to understand what is going on.

The most recent gamma-ray data from SN 2023ixf will be published in Astronomy and Astrophysics in a paper led by Martí-Devesa.

The post The Mystery of Cosmic Rays Deepens appeared first on Universe Today.

The ocean holds about 97 percent of Earth's water and covers 70 percent of our planet's surface. According to the United Nations, the ocean may be home to 50 to 80 percent of all life on Earth. Even if you live hundreds of miles from a coast, what happens in the ocean is fundamental to your life.

NASA is in the business of launching things into orbit. But what goes up must come down, and if whatever is coming down doesn’t burn up in the atmosphere, it will strike Earth somewhere.

Even Florida isn’t safe.

Careful consideration goes into releasing debris from the International Space Station. Its mass is measured and calculated so that it burns up during re-entry to Earth’s atmosphere. But in March 2024, something didn’t go as planned.

It all started in 2021 when astronauts replaced the ISS’s nickel hydride batteries with lithium-ion batteries. It was part of a power system upgrade, and the expired batteries added up to about 2,630 kg (5,800 lbs.) On March 8th, 2021, ground controllers used the ISS’s robotic arm to release a pallet full of the expired batteries into space, where orbital decay would eventually send them plummeting into Earth’s atmosphere.

The Canadarm 2 robotic arm releases a pallet of spent batteries into space on March 8th, 2021. Image Credit: NASA

It was the most massive debris release from the ISS. According to calculations, it should have burned up when it entered the atmosphere on March 8th, 2024. But it didn’t.

Alejandro Otero owns a home in Naples, Florida. He wasn’t home on March 8th when there was a loud crash as something smashed into his roof. But his son was. “It was a tremendous sound. It almost hit my son,” Otero told CNN affiliate WINK News in March. “He was two rooms over and heard it all.”

“Something ripped through the house and then made a big hole in the floor and on the ceiling,” Otero explained. “I’m super grateful that nobody got hurt.”

This time, nobody got hurt. But NASA is taking the accident seriously.

Otero cooperated with NASA, and NASA examined the object at the Kennedy Space Center in Florida. They determined the debris was from a stanchion used to mount the old batteries on a special cargo pallet.

This image shows an intact stanchion and the recovered stanchion from the NASA flight support equipment used to mount International Space Station batteries on a cargo pallet. The stanchion survived re-entry through Earth’s atmosphere on March 8, 2024, and impacted a home in Naples, Florida. Image Credit: NASA

The stanchion is made of the superalloy Inconel to understand extreme environments, including extreme heat. It weighs 725 grams (1.6 lbs.) It’s about 10 cm (4 inches) in height and 4 cm (1.6 inches) in diameter.

Even though it’s a tiny object, it’s the type of accident that NASA and the ISS are determined to avoid. “The International Space Station will perform a detailed investigation of the jettison and re-entry analysis to determine the cause of the debris survival and to update modelling and analysis, as needed,” a NASA statement read.

Investigators want to know how the debris survived without burning up on re-entry. Engineers use models to understand how objects react to re-entry heat and break apart, and this event will refine those models. In fact, every time an object reaches the ground, the models are updated.

For Otero, this accident amounted to little more than a great story and an insurance claim. But the chunk of stanchion could’ve seriously injured someone or even killed someone.

In January 1997, Lottie Williams was walking through a park with friends in Tulsa, Oklahoma, in the early morning. They saw a huge fireball in the sky and felt a rush of excitement, thinking they were seeing a shooting star. “We were stunned, in awe,” Williams told FoxNews.com. “It was beautiful.”

Then, something struck her lightly on the shoulder before falling to the ground. It was like a piece of metallic fabric, and after reaching out to some authorities, she learned that it was part of a fuel tank from a Delta II rocket. She’s the first person known to have been hit with space debris. Had it been something with more mass, who knows if Williams would’ve been injured or worse?

That’s why NASA takes debris survival so seriously. The guilt of injuring or even killing someone would be overwhelming. A serious debris accident could also make things very uncomfortable going forward, as people can be fickle and not prone to critical thinking. NASA’s already struggling with budget constraints; the organization doesn’t need any nasty public relations to imperil its progress further.

Complicating matters is that the ESA warned that not all the battery debris would burn up. There wasn’t much else they could do. Fluctuating atmospheric drag made it impossible to predict where debris would strike Earth.

Those who follow space know how complicated and unpredictable this is. And they likewise know how improbable an injury is. But there’s always a non-zero chance of injury or death from space debris for someone going about their life here on the Earth’s surface. If that ever happened, the scrutiny would be intense.

Is it statistical fear-mongering to consider space debris striking someone, injuring them, or worse? Probably. When we see a shooting star in the sky, it’s safe to enjoy the spectacle without worry.

But maybe, just in case, out of an abundance of caution, Don’t Look Up.

The post NASA Confirms that a Piece of its Battery Pack Smashed into a Florida Home appeared first on Universe Today.

The vertebrae of Vasuki indicus, a snake that lived 47 million years ago, suggest it could have been as long as 15 metres

The vertebrae of Vasuki indicus, a snake that lived 47 million years ago, suggest it could have been as long as 15 metres

The search for alien life can now include purple bacteria, thanks to a new catalog of chemical makeup of the lavender-hued organisms.

An exclusive interview with Zack Snyder about "Rebel Moon — Part Two: The Scargiver."

Russia's Angara A5 rocket lifted off on April 11, marking the fourth launch of the first rocket developed by Russia since the fall of the USSR in 1991.

Fossilized vertebrae that were found in an Indian coal mine belonged to a gigantic and previously unknown snake species

'Devil Comet' 12P/Pons-Brooks is hurtling toward the sun where it will make its closest approach on April 21. We take a look at whether this celestial vagabond will survive.