Astro Blog

By Leah Crane , NewScientist.  Excerpt: Astronomers have found six new worlds that look like planets, but formed like stars. These so-called rogue worlds are between five and 15 times the mass of Jupiter, and one of them may even host the beginnings of a miniature solar system. ...From their observations, the researchers determined that planetary mass  brown dwarfs  make up about 10 per cent of the objects in NGC 1333. That is far more than expected based on models of star formation, so there may be extra processes, such as turbulence, that drive the formation of these rogue worlds. ...One of the brown dwarfs is particularly unusual – it has a ring of dust around it just like the one that formed the planets in our solar system. At about five Jupiter masses, it is  the smallest world  ever spotted with such a ring, and it may mark the beginnings of a strange, scaled-down planetary system around a failed star... .  Full article at https://www.newscientist.com...

By Vashan Wright ,  Matthias Morzfeld , and  Michael Manga , PNAS - Proceedings of the National Academy of Sciences.  Abstract: Large volumes of liquid water transiently existed on the surface of Mars more than 3 billion years ago. Much of this water is hypothesized to have been sequestered in the subsurface or lost to space. We use rock physics models and Bayesian inversion to identify combinations of lithology, liquid water saturation, porosity, and pore shape consistent with the constrained mid-crust (∼11.5 to 20 km depths) seismic velocities and gravity near the InSight lander. A mid-crust composed of fractured igneous rocks saturated with liquid water best explains the existing data. Our results have implications for understanding Mars’ water cycle, determining the fates of past surface water, searching for past or extant life, and assessing in situ resource utilization for future missions.  Full article at https://www.pnas.org/doi/10.1073/pnas.24...

By Daniel Clery , Science.  Excerpt: For years, astronomers thought it was the Milky Way’s destiny to collide with its near neighbor the Andromeda galaxy a few billion years from now. But a new simulation finds a 50% chance the impending crunch will end up a near-miss, at least for the next 10 billion years. ...It’s been known that Andromeda is heading toward our home Galaxy since 1912, when astronomer Vesto Slipher noted that its light is blue-shifted.... ...It wasn’t until the era of orbiting observatories that astronomers could judge Andromeda’s overall velocity in 3D.... It was, they calculated, heading pretty much straight at the Milky Way at a speed of 110 kilometers per second. ...A  study from 2008  suggested a Milky Way–Andromeda merger was inevitable within the next 5 billion years...ending up in...the resulting elliptical, which the researchers dub “Milkomeda.” The Milky Way, seen today as a bright band across the sky, would be replaced by a “milky blob” markin...

By Hannah Richter , Science.  Excerpt: One of the classic tropes of science fiction is  terraforming Mars : warming up our cold neighbor so it could support human civilization. The idea might not be so far-fetched,  research published today  in Science Advances suggests. Injecting tiny particles into Mars’s atmosphere could warm the planet by more than 10°C in a matter of months, researchers find—enough to sustain liquid water. Although the scheme would require about 2 million tons of particles per year, they could be manufactured from readily available ingredients found in martian dust....  Full article at https://www.science.org/content/article/terraforming-mars-could-be-easier-scientists-thought . 

By Leonardo Carrer et al, Nature Astronomy.  Summary: Beneath the islands of Hawaii, there are systems of underground tunnels forged by fire: lava tubes or ‘pyroducts’ created by the islands’ volcanoes. ...New analyses suggest similar cavern networks born from moving magma exist on the Moon, and someday, ...may host life—ours. ...armed with newer analytical methods, researchers decided to re-examine data the Lunar Reconnaissance Orbiter’s miniature radio-frequency instrument collected a decade and a half ago. The pattern in the radar reflections from the Mare Tranquillitatis pit—one of the  best contenders for a cave entrance discovered to date  —indicate that a network of caves does indeed lie below. “The most likely explanation for our observations is an empty lava tube,” said co-author Leonardo Carrer  in a statement . ...Given that the lunar surface is blasted by solar and cosmic radiation, anyone spending time on the Moon will need a base that’s well-shielded—a...

By RHETT ALLAIN , Wired.  Excerpt: Betelgeuse, ...red supergiant has dimmed repeatedly in the past few years, which could mean that it's ready to go full supernova quite soon—and by “soon” we mean within the next 10,000 years. ...If Betelgeuse does blow, it will be the brightest supernova ever witnessed by humans. ...A  supernova that was observed in 2015 (ASASSN-15h)  had a peak luminosity of around 2 x 10 38  watts. That's more power output than 500  billion  suns. It's crazy. Oh, you didn't see that one? Yeah, because it was in a different galaxy. Betelgeuse is in our back yard, astronomically speaking. ...to a Betelgeuse supernova... start with a luminosity of 2 x 10 38  watts, like that supernova in 2015. For the distance, I'm going to use 500 light-years. ...With that, the intensity of the light received by Earth would be 0.711 watts per square meter. ...Crunching the numbers gives me a brightness magnitude of –18.5—which ...will be by far the br...

By Katrina Miller , The New York Times.  Excerpt: China brought a capsule full of lunar soil from the far side of the moon down to Earth on Tuesday, achieving the latest success in an ambitious schedule to explore the moon and other parts of the solar system. The sample, retrieved by the China National Space Administration’s Chang’e-6 lander after a 53-day mission, highlights  China’s growing capabilities in space  and notches another win in a series of lunar missions that started in 2007 and have so far been executed almost without flaw....  Full article at https://www.nytimes.com/2024/06/25/science/change-6-china-earth-moon.html .