Phys.org Astronomy and Space

• AI accelerates elucidation of nuclear forces with explosive neutron star data

  A research team is using astrophysical explosions to understand the mysterious forces at work in some of the smallest building blocks in nature: atomic nuclei. In new research published in Nature Communications, the team uses machine learning and artificial intelligence to decipher the data from astrophysical observations to better understand how neutrons and protons interact in dense matter at the quantum level.

• Galactic islands of tranquility: 'Little red dots' may have brewed life's building blocks

  Astronomers have found that both the core of our Milky Way and the earliest proto-galaxies in the universe share a surprising trait: They are unusually calm and quiet in terms of harsh radiation. This tranquility is not just a cosmic curiosity; it may be essential for forming complex molecules that provide the ingredients of life.

• Webb spots details in nearby spiral galaxy NGC 5134

  Two powerful instruments of the NASA/ESA/CSA James Webb Space Telescope joined forces to create this scenic galaxy view. This spiral galaxy is named NGC 5134, and it is located 65 million light-years away in the constellation Virgo. Though 65 million light-years may seem like a huge distance—the light that Webb collected to create this image has been journeying to us from NGC 5134 since soon after Tyrannosaurus rex went extinct—NGC 5134 is fairly close by as far as galaxies go. Because of the galaxy's relative proximity, Webb can spot incredible details in its tightly wound spiral arms.

• NASA clears its Artemis moon rocket for an April launch with four astronauts following repairs

  NASA cleared its moon rocket on Thursday for an April launch with four astronauts after completing the latest round of repairs.

• Deep underground, a telescope may soon detect ghosts of stars that died before Earth existed

  Imagine looking up at the night sky and seeing a star suddenly burst into a blaze of light brighter than anything nearby. A flash so bright that it briefly outshines an entire galaxy before fading forever.

• NASA's tiny spacecraft sends first exoplanet images

  With the first images from the spacecraft now in hand, the team behind NASA's Star-Planet Activity Research CubeSat, or SPARCS, is ready to begin charting the energetic lives of the galaxy's most common stars to help answer one of humanity's most profound questions: Which distant worlds beyond our solar system might be habitable?

• 'Ionic liquids' could redefine the habitable zone

  "Follow the water" has been a guiding mantra of astrobiology, and even space exploration more generally, for decades. If you want to find life, it makes sense to look for the universal solvent that almost all types of life on Earth use. But what if life doesn't actually need water to live or even evolve? A recent paper, available on the preprint server arXiv by researchers at MIT, including Dr. Sara Seager, and the University of Cardiff, proposes an alternative to water as the basis for life—ionic liquids (ILs) and deep eutectic solvents (DES).

• NASA plans to have a permanent base on the moon by 2030: How it can be done

  A US Senate committee has directed NASA to begin work on a moon base "as soon as is practicable." Under legislation advanced by the Senate lawmakers, the outpost would serve as a science laboratory and proving ground, where astronauts would develop the capabilities to live and work beyond Earth's orbit.

• Astronomers discuss fortifying our planetary defenses

  When people think of asteroids, they tend to picture rare, civilization-ending impacts like those depicted in movies such as "Armageddon." In reality, the asteroids most likely to affect modern society are much smaller. While kilometer-scale impacts occur only every tens of millions of years, decameter-scale (building-sized) objects strike Earth far more frequently: roughly every couple decades. As astronomers develop new ways to detect and track these smaller asteroids, planetary defense becomes increasingly relevant for protecting the space-based infrastructure that underpins modern life, from GPS navigation to global communications.

• Old NASA science satellite plunges back to Earth

  An old NASA science satellite plunged uncontrolled from orbit and reentered over the Pacific on Wednesday.

• We are not alone: Our sun escaped together with stellar 'twins' from galaxy center

  Researchers have uncovered evidence for our sun joining a mass migration of similar "twins" leaving the core regions of our galaxy, 4 to 6 billion years ago. The team created and studied an unprecedentedly accurate catalog of stars and their properties using data from the European Space Agency's Gaia satellite. Their discovery sheds light on the evolution of our galaxy, particularly the development of the rotating bar-like structure at its center.

• The Rubin Observatory's LSST will detect imminent impactors before they crash into Earth

  The Vera Rubin Observatory (VRO) has barely begun observations and is already wowing us. Images like its Cosmic Treasure Chest have us anticipating even more cosmic glory. And when the observatory sent out 800,000 alerts in one night in February, we got a taste of the scientific boost it will give astronomers. But while it's being lauded for its upcoming contributions to dark energy, supernovae, active galactic nuclei, and other distant and foundational subjects, it will also make important discoveries much closer to home. Its Legacy Survey of Space and Time (LSST) will find asteroids by the millions, and potentially dangerous Near-Earth Objects (NEO) by the tens of thousands.

• Galaxy-group motion suggests slower expansion in our cosmic neighborhood

  Two new studies have measured the expansion of the universe in our immediate cosmic neighborhood using a novel method that analyzes the motion of two nearby galaxy groups within their surrounding cosmic flow. The results indicate that the local universe is expanding more slowly than previously estimated, bringing measurements of nearby galaxies into close agreement with observations of the early universe. The findings also suggest that less dark matter is required to explain the dynamics of galaxies within these groups than previously assumed.

• Astronomers collect rare evidence of two planets colliding

  Anastasios (Andy) Tzanidakis was combing through old telescope data from 2020 when he found an otherwise boring star acting very strangely. The star, named Gaia20ehk, was about 11,000 light-years from Earth near the constellation Puppis. It was a stable "main sequence" star, much like our sun, which meant that it should emit steady, predictable light. Yet this star began to flicker wildly.

• Astronomers capture birth of a magnetar, confirming link to some of universe's brightest exploding stars

  Astronomers have for the first time seen the birth of a magnetar—a highly magnetized, spinning neutron star—and confirmed that it's the power source behind some of the brightest exploding stars in the cosmos. The finding corroborates a theory proposed by a UC Berkeley physicist 16 years ago and establishes a new phenomenon in exploding stars: supernovae with a "chirp" in their light curve that is caused by general relativity. A paper describing the phenomenon was published in the journal Nature.

• Hydrogen atmosphere could keep exomoons habitable for billions of years

  Liquid water is considered essential for life. Surprisingly, however, stable conditions that are conducive to life could exist far from any sun. A research team from the Excellence Cluster ORIGINS at LMU and the Max Planck Institute for Extraterrestrial Physics (MPE) has shown that moons around free-floating planets can keep their water oceans liquid for up to 4.3 billion years by virtue of dense hydrogen atmospheres and tidal heating—that is to say, for almost as long as Earth has existed and sufficient time for complex life to develop.

• Oval orbit casts new light on black hole–neutron star mergers

  Scientists have uncovered the first robust evidence of a black hole and neutron star crashing together but orbiting in an oval path rather than a perfect circle just before they merged. This discovery challenges long-standing assumptions about how these cosmic pairs form and evolve.

• How jagged moon dust could support future astronauts

  Lunar dust can be a pain—but it's also literally the ground we will have to traverse if we are ever to have a permanent human settlement on the moon. In that specific use case, its clingy, jagged, staticky properties can actually be an advantage, according to a new paper recently published in Research from scientists at Beihang University, who analyzed the mechanical properties of samples returned by the Chang'e 6 mission to the far side of the moon.

• NASA finds extreme star collision in unlikely spot

  A fleet of NASA missions has likely uncovered a collision between two ultradense stars in a tiny galaxy buried in a huge stream of gas. Astronomers have never seen this type of explosive event in an environment like this before—and it may help solve two outstanding cosmic mysteries. A paper describing these results is forthcoming in The Astrophysical Journal Letters and currently available on the arXiv preprint server.

• A new model defines an upper limit to planetary radiation belt intensity

  We all know that stars radiate light and much more. But radiation belts can also surround many other celestial bodies, such as planets. These belts do not generate particles themselves—the belts receive them from nearby stars—but they accelerate the speed of particles in a way that has remained elusive.

• New exoplanet survey method finds high rates of closely orbiting planets

  Up until now, exoplanet surveys have mostly focused on nearby, bright stars that are sun-like or are red dwarfs, which are known to frequently host planets. While astronomers have discovered thousands of planets this way, a new study, published in the Monthly Notices of the Royal Astronomical Society, seems to have found a more efficient way of detecting planets that orbit close to their stars.

• Astrophysicists trace the origin of valuable metals in space, from colliding stars to merging galaxies

  Billions of light years away in a remote part of the universe, two neutron stars—the ultradense remnants of dead stars—collided. The catastrophic cosmic event sent light and particles, including a sudden flash of gamma rays, streaming through the universe. These gamma rays traveled for 8.5 billion years before reaching Earth.

• European Space Agency probing fireball that hit German home

  The European Space Agency said it is investigating a fireball that streaked across the skies of Europe on the weekend before reportedly punching a football-sized hole in the roof of a German home.

• NASA's Van Allen Probe A to re-enter atmosphere

  NASA's Van Allen Probe A is expected to reenter Earth's atmosphere almost 14 years after launch. From 2012 to 2019, the spacecraft and its twin, Van Allen Probe B, flew through the Van Allen belts, rings of charged particles trapped by Earth's magnetic field, to understand how particles were gained and lost. The belts shield Earth from cosmic radiation, solar storms, and the constantly streaming solar wind that are harmful to humans and can damage technology, so understanding them is important.

• Strange cosmic burst from colliding galaxies shines light on heavy elements

  A recently detected flash of energy appears to have emanated from the wreckage of colliding galaxies, according to an international team of astronomers led by Penn State scientists. The burst, known as GRB 230906A, was likely caused by the collision of two neutron stars hundreds of millions of years ago and is now shedding light on how the universe creates some of its heaviest elements.

• Evaluating landing sites for China's manned moon mission

  Observations of the Rimae Bode region on the moon reveal five distinct types of terrain and identify several potential landing sites for China's first crewed mission, according to research titled "Geology of Rimae Bode region as priority site candidate for China's first crewed lunar mission." The work is published in Nature Astronomy.

• How do we know what asteroids are made out of?

  Asteroids are some of the oldest objects in the solar system: leftovers from the chaotic time when planets were assembling from dust and rock. They're time capsules, preserving clues about what the early solar system was like, and, ultimately, what the building blocks of planets are.

• Terraforming Mars isn't a climate problem—it's an industrial nightmare

  Even when the idea of terraforming Mars was originally put forward, the idea was daunting. Changing the environment of an entire planet is not something to do easily. Over the following decades, plenty of scientists and engineers have looked at the problem, and most have come to the same conclusion—we're not going to be able to make Mars anything like Earth anytime soon. A new paper available in pre-print on arXiv from Slava Turyshev of NASA's Jet Propulsion Laboratory is a good explainer as to why.

• Nearby red dwarf star hosts at least four planets—with one in the habitable zone

  In 2020, a study confirmed that two planets orbited the nearby red dwarf, GJ 887. Now, astronomers have confirmed the existence of two additional planets orbiting GJ 887 in a new study published in Astronomy and Astrophysics. The new study suggests that one of these newly confirmed planets is in the habitable zone.

• Record-energy neutrino may have begun its journey in blazars

  Three years ago, in the waters of the Mediterranean Sea, the passage of an "ultra-energetic" cosmic neutrino was observed—the most energetic ever detected. The event drew international attention from the scientific community as well as from the media and the public, not least because the origin of this particle—whose energy exceeded that of previously observed neutrinos by more than an order of magnitude—is unknown.