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Asteroid 2024 YR4 may hit Earth in 2032 – how worried should we be?

Fri, 07/02/2025 - 10:08

The risk of asteroid 2024 YR4 hitting Earth seems to be creeping up as astronomers gather more data, but does that mean we should be scrambling to prepare for an impact in 2032?

Millihertz oscillations near the innermost orbit of a supermassive black hole

Thu, 06/02/2025 - 10:23

Nature, Published online: 05 February 2025; doi:10.1038/s41586-024-08385-x

A millihertz frequency X-ray quasi-periodic oscillation has been observed near the innermost orbit of an actively accreting supermassive black hole and its frequency has evolved significantly over 2 years, a phenomenon that is difficult to explain with existing models.

Directly imaging the cooling flow in the Phoenix cluster

Thu, 06/02/2025 - 10:23

Nature, Published online: 05 February 2025; doi:10.1038/s41586-024-08369-x

Observations of the Phoenix cluster using the James Webb Space Telescope reveal rapid cooling in galaxy cluster cores, driven by black hole jets, with gas temperatures mapped between 105 K and 106 K and cooling rates of 5,000–23,000 M⊙ yr−1.

UN monitors asteroid with a tiny chance of hitting Earth

Thu, 06/02/2025 - 10:20

The asteroid named YR4 has a 1% chance of hitting Earth in 2032

Grand Canyons on the Moon

Wed, 05/02/2025 - 10:18

Nature, Published online: 04 February 2025; doi:10.1038/d41586-025-00263-4

How Grand Canyon-sized lunar-valleys could have been carved in mere minutes.

En Route to Jupiter, NASA’s Europa Clipper Captures Images of Stars

Wed, 05/02/2025 - 10:18

4 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater) This mosaic of a star field was made from three images captured Dec. 4, 2024, by star tracker cameras aboard NASA’s Europa Clipper spacecraft. Showing part of the constellation Corvus, it’s the first imagery of space the orbiter has captured since its launch on Oct. 14, 2024.NASA/JPL-Caltech This version of a mosaic captured by the star tracker cameras aboard NASA’s Europa Clipper on Dec. 4, 2024, features the names of stars within view of the cameras. NASA/JPL-Caltech

The spacecraft’s star trackers help engineers orient the orbiter throughout its long journey to Jupiter’s icy moon Europa.

Three months after its launch from NASA’s Kennedy Space Center in Florida, the agency’s Europa Clipper has another 1.6 billion miles (2.6 billion kilometers) to go before it reaches Jupiter’s orbit in 2030 to take close-up images of the icy moon Europa with science cameras.

Meanwhile, a set of cameras serving a different purpose is snapping photos in the space between Earth and Jupiter. Called star trackers, the two imagers look for stars and use them like a compass to help mission controllers know the exact orientation of the spacecraft — information critical for pointing telecommunications antennas toward Earth and sending data back and forth smoothly.

In early December, the pair of star trackers (formally known as the stellar reference units) captured and transmitted Europa Clipper’s first imagery of space. The picture, composed of three shots, shows tiny pinpricks of light from stars 150 to 300 light-years away. The starfield represents only about 0.1% of the full sky around the spacecraft, but by mapping the stars in just that small slice of sky, the orbiter is able to determine where it is pointed and orient itself correctly.

The starfield includes the four brightest stars — Gienah, Algorab, Kraz, and Alchiba — of the constellation Corvus, which is Latin for “crow,” a bird in Greek mythology that was associated with Apollo.

Engineers on NASA’s Europa Clipper mission work with the spacecraft’s star trackers in a clean room at the agency’s Jet Propulsion Laboratory in 2022. Used for orienting the spacecraft, the star trackers are seen here with red covers to protect their lenses.NASA/JPL-Caltech Hardware Checkout

Besides being interesting to stargazers, the photos signal the successful checkout of the star trackers. The spacecraft checkout phase has been going on since Europa Clipper launched on a SpaceX Falcon Heavy rocket on Oct. 14, 2024.

“The star trackers are engineering hardware and are always taking images, which are processed on board,” said Joanie Noonan of NASA’s Jet Propulsion Laboratory in Southern California, who leads the mission’s guidance, navigation and control operations. “We usually don’t downlink photos from the trackers, but we did in this case because it’s a really good way to make sure the hardware — including the cameras and their lenses — made it safely through launch.”

Pointing the spacecraft correctly is not about navigation, which is a separate operation. But orientation using the star trackers is critical for telecommunications as well as for the science operations of the mission. Engineers need to know where the science instruments are pointed. That includes the sophisticated Europa Imaging System (EIS), which will collect images that will help scientists map and examine the moon’s mysterious fractures, ridges, and valleys. For at least the next three years, EIS has its protective covers closed.

Europa Clipper carries nine science instruments, plus the telecommunications equipment that will be used for a gravity science investigation. During the mission’s 49 flybys of Europa, the suite will gather data that will tell scientists if the icy moon and its internal ocean have the conditions to harbor life.

The spacecraft already is 53 million miles (85 million kilometers) from Earth, zipping along at 17 miles per second (27 kilometers per second) relative to the Sun, and soon will fly by Mars. On March 1, engineers will steer the craft in a loop around the Red Planet, using its gravity to gain speed.

More About Europa Clipper

Europa Clipper’s three main science objectives are to determine the thickness of the moon’s icy shell and its interactions with the ocean below, to investigate its composition, and to characterize its geology. The mission’s detailed exploration of Europa will help scientists better understand the astrobiological potential for habitable worlds beyond our planet.

Managed by Caltech in Pasadena, California, JPL leads the development of the Europa Clipper mission in partnership with the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, for NASA’s Science Mission Directorate in Washington. APL designed the main spacecraft body in collaboration with JPL and NASA’s Goddard Space Flight Center in Greenbelt, Maryland, NASA’s Marshall Space Flight Center in Huntsville, Alabama, and Langley Research Center in Hampton, Virginia. The Planetary Missions Program Office at Marshall executes program management of the Europa Clipper mission. NASA’s Launch Services Program, based at Kennedy, managed the launch service for the Europa Clipper spacecraft.

Find more information about Europa Clipper here:

https://science.nasa.gov/mission/europa-clipper/

View an interactive 3D model of NASA’s Europa Clipper News Media Contacts

Gretchen McCartney
Jet Propulsion Laboratory, Pasadena, Calif.
818-287-4115
gretchen.p.mccartney@jpl.nasa.gov 

Karen Fox / Molly Wasser
NASA Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov  

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Grand canyons formed on moon in minutes after colossal asteroid strike

Wed, 05/02/2025 - 10:17

Two canyons that splay out from a vast asteroid crater on the moon may have been quickly formed by chains of impacts that followed the initial one

NASA’s InSight Finds Marsquakes From Meteoroids Go Deeper Than Expected

Tue, 04/02/2025 - 09:56

6 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater) Captured by the HiRISE camera on NASA’s Mars Reconnaissance Orbiter on March 4, 2021, this impact crater was found in Cerberus Fossae, a seismically active region of the Red Planet. Scientists matched its appearance on the surface with a quake detected by NASA’s InSight lander.NASA/JPL-Caltech/University of Arizona

With help from AI, scientists discovered a fresh crater made by an impact that shook material as deep as the Red Planet’s mantle.

Meteoroids striking Mars produce seismic signals that can reach deeper into the planet than previously known. That’s the finding of a pair of new papers comparing marsquake data collected by NASA’s InSight lander with impact craters spotted by the agency’s Mars Reconnaissance Orbiter (MRO).

The papers, published on Monday, Feb. 3, in Geophysical Research Letters (GRL), highlight how scientists continue to learn from InSight, which NASA retired in 2022 after a successful extended mission. InSight set the first seismometer on Mars, detecting more than 1,300 marsquakes, which are produced by shaking deep inside the planet (caused by rocks cracking under heat and pressure) and by space rocks striking the surface.

By observing how seismic waves from those quakes change as they travel through the planet’s crust, mantle, and core, scientists get a glimpse into Mars’ interior, as well as a better understanding of how all rocky worlds form, including Earth and its Moon.

A camera on the robotic arm of NASA’s InSight captured the lander setting down its Wind and Thermal Shield on Feb. 2, 2019. The shield covered InSight’s seismometer, which captured data from more than 1,300 marsquakes over the lander’s four-year mission.

Researchers have in the past taken images of new impact craters and found seismic data that matches the date and location of the craters’ formation. But the two new studies represent the first time a fresh impact has been correlated with shaking detected in Cerberus Fossae, an especially quake-prone region of Mars that is 1,019 miles (1,640 kilometers) from InSight.

The impact crater is 71 feet (21.5 meters) in diameter and much farther from InSight than scientists expected, based on the quake’s seismic energy. The Martian crust has unique properties thought to dampen seismic waves produced by impacts, and researchers’ analysis of the Cerberus Fossae impact led them to conclude that the waves it produced took a more direct route through the planet’s mantle.

InSight’s team will now have to reassess their models of the composition and structure of Mars’ interior to explain how impact-generated seismic signals can go that deep.

“We used to think the energy detected from the vast majority of seismic events was stuck traveling within the Martian crust,” said InSight team member Constantinos Charalambous of Imperial College London. “This finding shows a deeper, faster path — call it a seismic highway — through the mantle, allowing quakes to reach more distant regions of the planet.”

Spotting Mars Craters With MRO

A machine learning algorithm developed at NASA’s Jet Propulsion Laboratory in Southern California to detect meteoroid impacts on Mars played a key role in discovering the Cerberus Fossae crater. In a matter of hours, the artificial intelligence tool can sift through tens of thousands of black-and-white images captured by MRO’s Context Camera, detecting the blast zones around craters. The tool selects candidate images for examination by scientists practiced at telling which subtle colorations on Mars deserve more detailed imaging by MRO’s High-Resolution Imaging Science Experiment (HiRISE) camera.

“Done manually, this would be years of work,” said InSight team member Valentin Bickel of the University of Bern in Switzerland. “Using this tool, we went from tens of thousands of images to just a handful in a matter of days. It’s not quite as good as a human, but it’s super fast.”

Bickel and his colleagues searched for craters within roughly 1,864 miles (3,000 kilometers) of InSight’s location, hoping to find some that formed while the lander’s seismometer was recording. By comparing before-and-after images from the Context Camera over a range of time, they found 123 fresh craters to cross-reference with InSight’s data; 49 of those were potential matches with quakes detected by the lander’s seismometer. Charalambous and other seismologists filtered that pool further to identify the 71-foot Cerberus Fossae impact crater.

Deciphering More, Faster

The more scientists study InSight’s data, the better they become at distinguishing signals originating inside the planet from those caused by meteoroid strikes. The impact found in Cerberus Fossae will help them further refine how they tell these signals apart.

“We thought Cerberus Fossae produced lots of high-frequency seismic signals associated with internally generated quakes, but this suggests some of the activity does not originate there and could actually be from impacts instead,” Charalambous said.

The findings also highlight how researchers are harnessing AI to improve planetary science by making better use of all the data gathered by NASA and ESA (European Space Agency) missions. In addition to studying Martian craters, Bickel has used AI to search for landslides, dust devils, and seasonal dark features that appear on steep slopes, called slope streaks or recurring slope linae. AI tools have been used to find craters and landslides on Earth’s Moon as well.

“Now we have so many images from the Moon and Mars that the struggle is to process and analyze the data,” Bickel said. “We’ve finally arrived in the big data era of planetary science.”

More About InSight

JPL managed InSight for the agency’s Science Mission Directorate. InSight was part of NASA’s Discovery Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Alabama. Lockheed Martin Space in Denver built the InSight spacecraft, including its cruise stage and lander, and supported spacecraft operations for the mission.

A number of European partners, including France’s Centre National d’Études Spatiales (CNES) and the German Aerospace Center (DLR), supported the InSight mission. CNES provided the Seismic Experiment for Interior Structure (SEIS) instrument to NASA, with the principal investigator at IPGP (Institut de Physique du Globe de Paris). Significant contributions for SEIS came from IPGP; the Max Planck Institute for Solar System Research (MPS) in Germany; the Swiss Federal Institute of Technology (ETH Zurich) in Switzerland; Imperial College London and Oxford University in the United Kingdom; and JPL. DLR provided the Heat Flow and Physical Properties Package (HP3) instrument, with significant contributions from the Space Research Center (CBK) of the Polish Academy of Sciences and Astronika in Poland. Spain’s Centro de Astrobiología (CAB) supplied the temperature and wind sensors.

A division of Caltech in Pasadena, California, JPL manages the Mars Reconnaissance Orbiter Project for NASA’s Science Mission Directorate, Washington. The University of Arizona, in Tucson, operates HiRISE, which was built by BAE Systems in Boulder, Colorado. The Context Camera was built by, and is operated by, Malin Space Science Systems in San Diego. 

For more about Insight, visit:

https://science.nasa.gov/mission/insight/

For more about MRO, visit:

https://science.nasa.gov/mission/mars-reconnaissance-orbiter/

News Media Contacts

Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-2433
andrew.c.good@jpl.nasa.gov

Karen Fox / Molly Wasser
NASA Headquarters, Washington
202-358-1600
|karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov

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NASA’s ‘most prolific planet hunter so far’ — the story of the Kepler Space Telescope

Tue, 04/02/2025 - 09:55

Nature, Published online: 03 February 2025; doi:10.1038/d41586-025-00295-w

Ingenuity and decades of planning enabled the mission’s success.

Most detailed survey of particles around the sun reveals new mysteries

Tue, 04/02/2025 - 09:54

More than a decade of data about the particles zipping around our sun could be used to solve many mysteries, from the behaviour of individual particles to the history of our solar system – while raising new questions

UN monitors asteroid with a tiny chance of hitting Earth

Tue, 04/02/2025 - 09:53

The asteroid named YR4 has a 1% chance of hitting Earth in 2032

Asteroid contains building blocks of life, say scientists

Mon, 03/02/2025 - 10:38

Bennu contains minerals and thousands of organic molecules, including the chemical components that make up DNA.

AI to revolutionise fundamental physics and ‘could show how universe will end’

Mon, 03/02/2025 - 10:37

Exclusive: Cern’s next director general Mark Thomson says AI is paving the way for huge advances in particle physics

Advanced artificial intelligence is to revolutionise fundamental physics and could open a window on to the fate of the universe, according to Cern’s next director general.

Prof Mark Thomson, the British physicist who will assume leadership of Cern on 1 January 2026, says machine learning is paving the way for advances in particle physics that promise to be comparable to the AI-powered prediction of protein structures that earned Google DeepMind scientists a Nobel prize in October.

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6 Things to Know About SPHEREx, NASA’s Newest Space Telescope

Sat, 01/02/2025 - 09:07

5 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater) NASA’s SPHEREx observatory undergoes testing at BAE Systems in Boulder, Colorado, in August 2024. Launching no earlier than Feb. 27, 2025, the mission will make the first all-sky spectroscopic survey in the near-infrared, helping to answer some of the biggest questions in astrophysics. BAE Systems/NASA/JPL-Caltech

Shaped like a megaphone, the upcoming mission will map the entire sky in infrared light to answer big questions about the universe.

Expected to launch no earlier than Thursday, Feb. 27, from Vandenberg Space Force Base in California, NASA’s SPHEREx space observatory will provide astronomers with a big-picture view of the cosmos like none before. Short for Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer, SPHEREx will map the entire celestial sky in 102 infrared colors, illuminating the origins of our universe, galaxies within it, and life’s key ingredients in our own galaxy. Here are six things to know about the mission.

1. The SPHEREx space telescope will shed light on a cosmic phenomenon called inflation.

In the first billionth of a trillionth of a trillionth of a second after the big bang, the universe increased in size by a trillion-trillionfold. Called inflation, this nearly instantaneous event took place almost 14 billion years ago, and its effects can be found today in the large-scale distribution of matter in the universe. By mapping the distribution of more than 450 million galaxies, SPHEREx will help scientists improve our understanding of the physics behind this extreme cosmic event.

Go behind the scenes with the team working on NASA’s SPHEREx space telescope as they talk through their rigorous testing process. NASA/JPL-Caltech/BAE Systems 2. The observatory will measure the collective glow from galaxies near and far.

Scientists have tried to estimate the total light output from all galaxies throughout cosmic history by observing individual galaxies and extrapolating to the trillions of galaxies in the universe. The SPHEREx space telescope will take a different approach and measure the total glow from all galaxies, including galaxies too small, too diffuse, or too distant for other telescopes to easily detect. Combining the measurement of this overall glow with other telescopes’ studies of individual galaxies will give scientists a more complete picture of all the major sources of light in the universe.

3. The mission will search the Milky Way galaxy for essential building blocks of life.

Life as we know it wouldn’t exist without basic ingredients such as water and carbon dioxide. The SPHEREx observatory is designed to find these molecules frozen in interstellar clouds of gas and dust, where stars and planets form. The mission will pinpoint the location and abundance of these icy compounds in our galaxy, giving researchers a better sense of their availability in the raw materials for newly forming planets.

Molecular clouds like this one, called Rho Ophiuchi, are collections of cold gas and dust in space where stars and planets can form. SPHEREx will survey such regions through-out the Milky Way galaxy to measure the abundance of water ice and other frozen mole-cules. NASA/JPL-Caltech 4. It adds unique strengths to NASA’s fleet of space telescopes.

Space telescopes like NASA’s Hubble and Webb have zoomed in on many corners of the universe to show us planets, stars, and galaxies in high resolution. But some questions — like how much light do all the galaxies in the universe collectively emit? — can be answered only by looking at the big picture. To that end, the SPHEREx observatory will provide maps that encompass the entire sky. Objects of scientific interest identified by SPHEREx can then be studied in more detail by targeted telescopes like Hubble and Webb.

5. The SPHEREx observatory will make the most colorful all-sky map ever.

The SPHEREx observatory “sees” infrared light. Undetectable to the human eye, this range of wavelengths is ideal for studying stars and galaxies. Using a technique called spectroscopy, the telescope can split the light into its component colors (individual wavelengths), like a prism creates a rainbow from sunlight, in order to measure the distance to cosmic objects and learn about their composition. With SPHEREx’s spectroscopic map in hand, scientists will be able to detect evidence of chemical compounds, like water ice, in our galaxy. They’ll not only measure the total amount of light emitted by galaxies in our universe, but also discern how bright that total glow was at different points in cosmic history. And they’ll chart the 3D locations of hundreds of millions of galaxies to study how inflation influenced the large-scale structure of the universe today.

6. The spacecraft’s cone-shaped design helps it stay cold and see faint objects.

The mission’s infrared telescope and detectors need to operate at around minus 350 degrees Fahrenheit (about minus 210 degrees Celsius). This is partly to prevent them from generating their own infrared glow, which might overwhelm the faint light from cosmic sources. To keep things cold while also simplifying the spacecraft’s design and operational needs, SPHEREx relies on an entirely passive cooling system — no electricity or coolants are used during normal operations. Key to making this feat possible are three cone-shaped photon shields that protect the telescope from the heat of Earth and the Sun, as well as a mirrored structure beneath the shields to direct heat from the instrument out into space. Those photon shields give the spacecraft its distinctive outline.

More About SPHEREx

SPHEREx is managed by NASA’s Jet Propulsion Laboratory for the agency’s Astrophysics Division within the Science Mission Directorate at NASA Headquarters in Washington. BAE Systems (formerly Ball Aerospace) built the telescope and the spacecraft bus. The science analysis of the SPHEREx data will be conducted by a team of scientists located at 10 institutions in the U.S., two in South Korea, and one in Taiwan. Data will be processed and archived at IPAC at Caltech, which manages JPL for NASA. The mission principal investigator is based at Caltech with a joint JPL appointment. The SPHEREx dataset will be publicly available at the NASA/IPAC Infrared Science Archive.

For more information about the SPHEREx mission visit:

https://www.jpl.nasa.gov/missions/spherex

Video: Why SPHEREx looks the way it does News Media Contact

Calla Cofield
Jet Propulsion Laboratory, Pasadena, Calif.
626-808-2469
calla.e.cofield@jpl.nasa.gov

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Share Details Last Updated Jan 31, 2025 Related Terms Explore More 2 min read Hubble Spots a Supernova

The subject of this NASA/ESA Hubble Space Telescope image is a supernova-hosting galaxy located about…

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SPHEREx’s Concentric Cones

Fri, 31/01/2025 - 10:41
Short for Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer, SPHEREx will create a map of the cosmos like no other. Using a technique called spectroscopy to image the entire sky in 102 wavelengths of infrared light, SPHEREx will gather information about the composition of and distance to millions of galaxies and stars. With this map, scientists will study what happened in the first fraction of a second after the big bang, how galaxies formed and evolved, and the origins of water in planetary systems in our galaxy.NASA/JPL-Caltech/BAE Systems

NASA’s SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer) observatory rests horizontally in this April 2024 image taken at BAE Systems in Boulder, Colorado. This orientation shows the observatory’s three layers of photon shields – the metallic concentric cones.

Over a two-year planned mission, the SPHEREx Observatory will collect data on more than 450 million galaxies along with more than 100 million stars in the Milky Way in order to explore the origins of the universe.

Tune in at 12 p.m. EST Jan. 31, 2025, to hear agency experts preview the mission. SPHEREx is targeted to launch no earlier than Feb. 27, 2025.

Image credit: NASA/JPL-Caltech/BAE Systems

Flashes from ancient galaxy deepen mystery of fast radio bursts

Thu, 30/01/2025 - 10:16

Nature, Published online: 29 January 2025; doi:10.1038/d41586-025-00233-w

Unusual detection bolsters evidence that the mysterious signals can be caused by different astrophysical events.

An evaporite sequence from ancient brine recorded in Bennu samples

Thu, 30/01/2025 - 10:16

Nature, Published online: 29 January 2025; doi:10.1038/s41586-024-08495-6

Samples from the asteroid (101955) Bennu, returned by the OSIRIS-REx mission, include sodium-bearing phosphates and sodium-rich carbonates, sulfates, chlorides and fluorides formed during evaporation of a late-stage brine.

Asteroid fragments upend theory of how life on Earth bloomed

Thu, 30/01/2025 - 10:15

Nature, Published online: 29 January 2025; doi:10.1038/d41586-025-00264-3

Samples from Bennu contain the chemical building blocks of life — but with a twist.

Asteroid Bennu contains building blocks of life

Thu, 30/01/2025 - 10:15

Nature, Published online: 29 January 2025; doi:10.1038/d41586-025-00267-0

Bennu gives researchers clues about how the chemicals that make up life arose, how a maize monoculture might have supported a mysterious civilization and why the new AI model DeepSeek R1 has sent shockwaves around the world.

Asteroid Bennu contains salts from ancient brine

Thu, 30/01/2025 - 10:15

Nature, Published online: 29 January 2025; doi:10.1038/d41586-025-00084-5

A space mission to an asteroid has returned extremely delicate salts not previously observed in extraterrestrial materials. An analysis of these salts helps to establish the history of water in the early Solar System.