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It was larger than the Earth.

Northern lights don't usually reach this far south.

Right now, one of the largest sunspot groups in recent history is crossing the Sun.

Relax and watch two black holes merge.

The Galaxy, the Jet, and a Famous Black Hole

What would it look like to circle a black hole?

For the mostly harmless denizens of planet Earth, the

The one-day courses were particularly beneficial to those pupils with worse mental health problems initially

We have discovered over 5,000 planets around other star systems. Amongst the veritable cosmic menagerie of exoplanets, it seems there is a real shortage of Neptune-sized planets close to their star. A new paper just published discusses a Saturn-sized planet close to its host star which should be experiencing mass loss, but isn’t. Studying this world offers a new insight into exoplanet formation across the Universe. 

Exoplanets really are fascinating. Ever-since their discovery the race has been on to discover and catalogue them. It gives us a great opportunity to explore a far more statistically significant set of data to understand planetary system formation rather than just studying are own system.

The absence of Neptune-mass exoplanets closer to the host stars in exoplanetary systems has been a bit of a mystery. Their lack has been attributed to one of two things; photoevaporation – mass is lost through ionisation of gas by radiation which then disperses away form the ionising source or high-eccentricity migration – where the planets move through the planetary system as we have seen with some of the giant planets in our Solar System. 

NASA’s Voyager 2 spacecraft captured these views of Uranus (on the left) and Neptune (on the right) during its flybys of the planets in the 1980s.

To distinguish between these two possibilities a team of astronomers led by Morgan Saidel from the California Institute of Technology investigated the origins of TOI-1259 A b which is a Saturn mass exoplanet. It is in a 3.48 day orbit around a K type star at a distance putting it on the edge of the so called Neptune desert. A region around a star wherein there are no Neptune sized planets. 

In the case of TOI-1259 A b, it is thought that its low density means it is especially vulnerable to photoevaporation. Transit methods were used, observing with the Hale Telescope at Palomar Observatory in the 1083nm helium line to probe the upper levels of the atmosphere. The near-infrared spectrograph on Keck II was also used and showed that there was indeed atmosphere escaping but at a rate lower than expected. The rate of gas loss through photoevaporation (1010.325 g s?1)is too low to significantly have altered the planets mass even if it had formed in its current location.

The hexagonal primary mirror of the Keck II telescope. (Credit: SiOwl. A Wikimedia Commons image under a Creative Commons Attribution 3.0 Unported liscense).

Instead, the team believe that the presence of a white dwarf companion (TOI-1259 B) may have caused the planet to migrate inwards after formation. Analysing the orbital parameters of the planet and the binary star system reveal that high-eccentricity migration is a far more likely explanation. 

Planetary migrations of this sort may leave a trace through accretion of elements in the planetary atmosphere. Quantities of H2O, CO, CO2 , SO2 and CH4 should be at detectable levels in the atmosphere of TOI-1259 A b.  If they are observed through transmission spectroscopic studies, will reveal where in protoplanetary disk the planet formed in. Further studies will be required to finally answer this question. 

Source : Atmospheric Mass Loss from TOI-1259 A b, a Gas Giant Planet With a White Dwarf Companion

The post Saturn-Sized Exoplanet Isn’t Losing Mass Quickly Enough appeared first on Universe Today.

Satellite imagery of Rafah, Gaza, provided by commercial company Planet Labs, offers a spaceborne view of the Israel-Hamas war.

After much debate, the Curiosity Mars rover team decided to continue following an intriguing channel rather than send the robot on an off-road detour.

Eleasa Kim, stationed at NASA’s Marshall Space Flight Center, leads the Commercial Low Earth Orbit Development Program (CLDP) payload operations at Johnson Space Center, with 18 years of mission support under her belt. Her roles have included biomedical engineer flight controller, payload safety engineer for Artemis I, planning and analysis branch operations discipline lead, and glovebox integration engineer, with each enriching her understanding of engineering, safety, and leadership. 

Kim is currently working to ensure a smooth transition to commercial space operations for the science being conducted in microgravity for the benefit of humanity. 

Eleasa Kim tests eye imaging hardware for the astronauts to use aboard the International Space Station.

Kim evaluates plans and documentation for commercial space stations, prepares materials for research operations, and devises strategies to enhance partner success and sustain the low Earth orbit economy. “I love the trust and support we are provided to brainstorm and offer recommendations for transitioning space station operations to commercial platforms,” she said.  

As the lead of the Human Exploration and Development Office’s (HEDO) Unity Team at Marshall, Kim is championing a culture of safety and inclusivity while leading a group of 15 people that represent every office and branch within HEDO. Kim and her team are tackling complex topics to enhance organizational culture. “We are promoting inclusion of everyone and more education and communication on topics that are not easy to talk about,” she said. 

NASA’s Human Exploration and Development Office (HEDO) 2024 Unity Team at their kickoff meeting. From left: Sheena Hawthorne, Eleasa Kim, Glenn Medina, Johnathan Carlson, Jennifer Christopher, Jenni Deylius, Carol Reynolds, Brooke Thornton, Sherresa Lockett, April Hargrave, Phillippia Simmons, DeAnna Whitehead, Tishawn Webb, Stacey Kelley, Ginger Flores, Wendy Cruit, and Luke Bingaman.

“A large part of my identity is recognizing that people come first,” said Kim. “I take the opportunities to connect with and meet people where they are. I try to figure out how I can add value.” 

Although it is tough for her to pick her favorite project or program she has worked on at NASA, one of her most cherished experiences was during her tenure as an International Space Station biomedical engineer, where she completed a parabolic flight to test vital crew health support hardware. “My favorite part was learning what it meant to have a family at work that I trusted and could count on,” she said.  

Eleasa Kim performs inverted CPR in a zero-gravity parabolic flight.

In her other previous roles, she most enjoyed learning about science experiments as a payloads planner and playing a critical role in their success. As a payload safety engineer for Artemis I, she loved being able to deep dive into complex and specific problems and learn about safety risk and probability. As the planning and analysis branch operations discipline lead at Marshall, Kim says she loved learning about analyzing performance metrics, reporting, and providing leadership to multiple teams. 

Kim emphasizes the importance of staying curious and adaptable, recognizing that each role and team presents unique cultural and technical challenges. She says, “When faced with a challenge, I can overcome a lot more than I think by asking myself, ‘How can I do this?’”  

Eleasa Kim served as the International Space Station lead biomedical engineer for Space Shuttle mission STS-119. Credit: NASA/Devin Boldt

She has supported real-time mission operations, pre-mission planning, safety, engineering, and project management roles. “It takes time to get oriented each time I move into a team,” she said. “While challenging, it is also very exciting and motivating for me because I’m passionate about knowing people and learning new things.” 

Kim believes that NASA is actively driving change, emphasizing the importance of consistent communication from every individual. This approach, reminiscent of “boots on the ground,” is reshaping the agency’s culture from its foundation. “We can and are changing the culture from the bottom up, and NASA is providing the enabling function of management support,” she said. “We need to provide safe spaces for people to be vulnerable and help ensure everyone feels safe to contribute.”  

Eleasa Kim during a ski trip with her two children.

Kim’s cultural heritage is rooted in South Korea, where her parents originated before emigrating to the United States. Raised in America, she has a profound appreciation for Korean culture, especially its cuisine, and enjoys cooking traditional meals and sharing them with friends and colleagues. 

Kim says she is most proud of being a mother of two kind, beautiful, sharp, strong-willed, and passionate girls. 

She hopes to pass on to the next generation the inspiration to do great things for all of humanity, as did those who came before us. “I am excited to see what commercial and international growth will bring in the next decade.” 

Gravitational wave astronomy has been one of the hottest new types of astronomy ever since the LIGO consortium officially detected the first gravitational wave (GW) back in 2016. Astronomers were excited about the number of new questions that could be answered using this sensing technique that had never been considered before. But a lot of the nuance of the GWs that LIGO and other detectors have found in the 90 gravitational wave candidates they have found since 2016 is lost. 

Researchers have a hard time determining which galaxy a gravitational wave comes from. But now, a new paper from researchers in the Netherlands has a strategy and developed some simulations that could help narrow down the search for the birthplace of GWs. To do so, they use another darling of astronomers everywhere—gravitational lensing.

Importantly, GWs are thought to be caused by merging black holes. These catastrophic events literally distort space-time to the point where their merger causes ripples in gravity itself. However, those signals are extraordinarily faint when they reach us—and they are often coming from billions of light-years away. 

Detectors like LIGO are explicitly designed to search for those signals, but it’s still tough to get a strong signal-to-noise ratio. Therefore, they’re also not particularly good at detailing where a particular GW signal comes from. They can generally say, “It came from that patch of sky over there,” but since “that patch of sky” could contain billions of galaxies, that doesn’t do much to narrow it down.

Fraser discusses the crazy physics that happen when black holes run into each other.

But astronomers lose a lot of context regarding what a GW can tell them about its originating galaxy if they don’t know what galaxy it came from. That’s where gravitational lensing comes in.

Gravitational lenses are a physical phenomenon whereby the signal (in most cases light) coming from a very faraway object is warped by the mass of an object that lies between the further object and us here on Earth. They’re responsible for creating “Einstein Rings,” some of the most spectacular astronomical images.

Light is not the only thing that can be affected by mass, though—gravitational waves can, too. Therefore, it is at least possible that gravitational waves themselves could be warped by the mass of an object between it and Earth. If astronomers are able to detect that warping, they can also tell which specific galaxy in an area of the sky the GW sign is coming from. 

Once astronomers can track down the precise galaxy, creating a gravitational wave, the sky is (not) the limit. They can narrow down all sorts of characteristics not only of the wave-generating galaxy itself but also of the galaxy in front of it, creating the lens. But how exactly should astronomers go about doing this work?

Fraser celebrates the workhorses of the GW detector stable – LIGO and VIRGO – coming back online after upgrades.

That is the focus of the new paper from Ewoud Wempe, a PhD student at the University of Groningen, and their co-authors. The paper details several simulations that attempt to narrow down the origin of a lensed gravitational wave. In particular, they use a technique similar to the triangulation that cell phones use to determine where exactly they are in relation to GPS satellites. 

Using this technique can prove fruitful in the future, as the authors believe there are as many as 215,000 potential GW lensed candidates that would be detectable in data sets from the next generation of GW detectors. While those are still coming online, the theoretical and modeling worlds remain hard at work trying to figure out what kind of data would be expected for different physical realities of this newest type of astronomical observation.

Learn More:
Wempe et al. – On the detection and precise localization of merging black holes events through strong gravitational lensing
UT – After Decades of Observations, Astronomers have Finally Sensed the Pervasive Background Hum of Merging Supermassive Black Holes
UT – A Neutron Star Merged with a Surprisingly Light Black Hole
UT – When Black Holes Merge, They’ll Ring Like a Bell

Lead Image:
Example of a gravitational lens.
Credit – Hubble Telescope / NASA / ESA

The post Gravitational Lenses Could Pin Down Black Hole Mergers with Unprecedented Accuracy appeared first on Universe Today.

Blue Origin is targeting Sunday (May 19) for the six-person NS-25, the company's first crewed spaceflight since August 2022.

The TRAPPIST-1 solar system generated a swell of interest when it was observed several years ago. In 2016, astronomers using the Transiting Planets and Planetesimals Small Telescope (TRAPPIST) at La Silla Observatory in Chile detected two rocky planets orbiting the red dwarf star, which took the name TRAPPIST-1. Then, in 2017, a deeper analysis found another five rocky planets.

It was a remarkable discovery, especially because up to four of them could be the right distance from the star to have liquid water.

The TRAPPIST-1 system still gets a lot of scientific attention. Potential Earth-like planets in a star’s habitable zone are like magnets for planetary scientists.

Finding seven of them in one system is a unique scientific opportunity to examine all kinds of interlinked questions about exoplanet habitability. TRAPPIST-1 is a red dwarf, and one of the most prominent questions about exoplanet habitability concerns red dwarfs (M dwarfs.) Do these stars and their powerful flares drive the atmospheres away from their planets?

New research in the Planetary Science Journal examines atmospheric escape on the TRAPPIST-1 planets. Its title is “The Implications of Thermal Hydrodynamic Atmospheric Escape on the TRAPPIST-1 Planets.” Megan Gialluca, a graduate student in the Department of Astronomy and Astrobiology Program at the University of Washington, is the lead author.

Most stars in the Milky Way are M dwarfs. As the TRAPPIST-1 makes clear, they can host many terrestrial planets. Large, Jupiter-size planets are comparatively rare around these types of stars.

artist concepts of the seven planets of TRAPPIST-1 with their orbital periods, distances from their star, radii and masses as compared to those of Earth. Credit: NASA/JPL

It’s a distinct possibility that most terrestrial planets are in orbit around M dwarfs.

But M dwarf flaring is a known issue. Though M dwarfs are far less massive than our Sun, their flares are way more energetic than anything that comes from the Sun. Some M dwarf flares can double the star’s brightness in only minutes.

Another problem is tidal locking. Since M dwarfs emit less energy, their habitable zones are much closer than the zones around a main sequence star like our Sun. That means potentially habitable planets are much more likely to be tidally locked to their stars.

That creates a whole host of obstacles to habitability. One side of the planet would bear the brunt of the flaring and be warmed, while the other side would be perpetually dark and cold. If there’s an atmosphere, there could be extremely powerful winds.

“As M dwarfs are the most common stars in our local stellar neighbourhood, whether their planetary systems can harbour life is a key question in astrobiology that may be amenable to observational tests in the near term,” the authors write. “Terrestrial planetary targets of interest for atmospheric characterization with M dwarf hosts may be accessible with the JWST,” they explain. They also point out that future large ground-based telescopes like the European Extremely Large Telescope and the Giant Magellan Telescope could help, too, but they’re years away from being operational.

This is an artist’s impression of the TRAPPIST-1 system, showing all seven planets. Image Credit: NASA

Red dwarfs and their planets are easier to observe than other stars and their planets. Red dwarfs are small and dim, meaning their light doesn’t drown out planets as much as other main-sequence stars do. But despite their lower luminosity and small size, they present challenges to habitability.

M dwarfs have a longer pre-main-sequence phase than other stars and are at their brightest during this time. Once they’re on the main sequence, they have heightened stellar activity compared to stars like our Sun. These factors can both drive atmospheres away from nearby planets. Even without flaring, the closest planet to TRAPPIST-1 (T-1 hereafter) receives four times more radiation than Earth.

“In addition to luminosity evolution, heightened stellar activity also increases the stellar XUV of M dwarf stars, which enhances atmospheric loss,” the authors write. This can also make it difficult to understand the spectra from planetary atmospheres by creating false positives of biosignatures. Exoplanets around M dwarfs are expected to have thick atmospheres dominated by abiotic oxygen.

Despite the challenges, the T-1 system is a great opportunity to study M dwarfs, atmospheric escape, and rocky planet habitability. “TRAPPIST-1 is a high-priority target for JWST General and Guaranteed Time Observations,” the authors write. The JWST has observed parts of the T-1 system, and that data is part of this work.

In this work, the researchers simulated early atmospheres for each of the TRAPPIST-1 (T-1 hereafter) planets, including different initial water amounts expressed in Terrestrial Oceans (TO.) They also modelled different amounts of stellar radiation over time. Their simulations used the most recent data for the T-1 planets and used a variety of different planetary evolution tracks.

In this research, the authors took into account the predicted present-day water content for each of the outer planets and then worked backwards to understand their initial water content. This figure shows “The likelihood of each initial water content (in TO) needed to reproduce the predicted present-day water contents for each of the outer planets,” the authors write. The four outer planets would’ve started out with enormous amounts of water compared to Earth. Image Credit: Gialluca et al. 2024.

The results are not good, especially for the planets closest to the red dwarf.

“We find the interior planets T1-b, c, and d are likely desiccated for all but the largest initial water contents (>60, 50, and 30 TO, respectively) and are at the greatest risk of complete atmospheric loss due to their proximity to the host star,” the researchers explain. However, depending on their initial TO, they could retain significant oxygen. That oxygen could be a false positive for biosignatures.

The outer planets fare a little better. They could retain some of their water unless their initial water was low at about 1 TO. “We find T1-e, f, g, and h lose, at most, approximately 8.0, 4.8, 3.4, and 0.8 TO, respectively,” they write. These outer planets probably have more oxygen than the inner planets, too. Since T1-e, f, and g are in the star’s habitable zone, it’s an intriguing result.

T-1c is of particular interest because, in their simulations, it retains the most atmospheric oxygen regardless of whether the initial TO was high or low.

This artist’s illustration shows what the hot rocky exoplanet TRAPPIST-1 c could look like. Image Credit: By NASA, ESA, CSA, Joseph Olmsted (STScI) – https://webbtelescope.org/contents/media/images/2023/125/01H2TJJF981PWQK9YT0VGH2HPV, Public Domain, https://commons.wikimedia.org/w/index.php?curid=133303919

The potential habitability of T-1 planets is an important question in exoplanet science. The type of star, the number of rocky planets, and the ease of observation all place it at the top of the list of observational targets. We’ll never really understand exoplanet habitability if we can’t understand this system. The only way to understand it better is to observe it more thoroughly.

“These conclusions motivate follow-up observations to search for the presence of water vapour or oxygen on T1-c and future observations of the outer planets in the TRAPPIST-1 system, which may possess substantial water,” the authors write in their conclusion.

The post TRAPPIST-1 Outer Planets Likely Have Water appeared first on Universe Today.

A car-sized asteroid flew very close to Earth on Tuesday morning (May 14), just two days after being discovered.

This large constellation abounds in deep-sky delights, including many fine open star clusters.

The post Explore the Star Clusters of Centaurus appeared first on Sky & Telescope.

A monster sunspot on the sun's surface just won't quit, erupting yet again this week with a whopping X8.7-class solar flare on Tuesday (May 14).

NASA's Juno spacecraft has spotted the elusive fifth moon of Jupiter transiting the giant planet's Great Red Spot, giving astronomers a rare view of this small but intriguing natural satellite.

Engineers test the VIPER rover’s wheel movement and rotation in a clean room at NASA’s Johnson Space Center in Houston.NASA/Helen Arase Vargas

While NASA’s VIPER team has been focused on building the flight rover that will go to the South Pole of the Moon, the team has also been making preparations for environmental testing of the rover. 

In April, the VIPER team passed a System Test Readiness Review, exploring the readiness of the facilities, procedures, and staff to move into stress-testing the VIPER rover.

These environmental tests are important because they force our rover to experience the conditions it will see during launch, landing, and in the thermal environment of operating at the lunar South Pole. Specifically, acoustic testing will simulate the harsh, vibrational “rock concert” experience of launch, while thermal-vacuum testing will expose VIPER to the hottest and coldest temperatures it will see during the mission, all while operating in the vacuum of space. It’s a tough business, but we have to make sure we’re up for it.

Thanks to this team for the hard efforts to get to this important phase in mission readiness!

Go VIPER!

– Dan Andrews, VIPER Project Manager