Astro Blog

By  Jamie M. Jasinsk  et al, Nature Astronomy. Summary: A human spacecraft has only gotten close to Uranus once—in 1986, when Voyager 2 drifted past the distant planet. That flyby indicated that   Uranus was weird in several ways , which astronomers have spent decades trying to explain. Now, a new analysis in   Nature Astronomy   suggests the probe   just happened to arrive there on an off day . Voyager 2’s data indicated that Uranus had an “unusually oblique and off-centered magnetic field” with inexplicably intense electron radiation belts and a severely plasma-depleted magnetosphere,” the team behind the new work writes. But by mining old data from the mission, the scientists found evidence for a super strong solar wind that likely squished the magnetosphere just prior to the probe’s readings. This would have pushed any plasma too close to the planet to detect, and filled the radiation belts with high-energy particles. https://www.nature.com/articles/s41550-024-02389-3?et_rid=401791

By Saima May Sidik , Eos/AGU.  Excerpt: Geological evidence on Mars indicates that 3.6 billion years ago, an intense pulse of water carved rivers and lakes across the planet, an abrupt shift from the preceding 500-million-year era of much gentler fluvial activity. Researchers have long  puzzled over  the cause. A new study by  Buhler  shows, paradoxically, that the collapse of the Martian atmosphere and entry into a  colder  climate may have melted the polar ice cap and triggered global-scale flooding. ...In total, about 4% to 40% of the water ice could have melted, an amount of water equivalent to between 20% and 200% of the  water currently found near the surface on Mars ....  Full article at https://eos.org/research-spotlights/how-an-ocean-sized-lake-may-have-formed-on-ancient-mars . 

By Damond Benningfield , Eos/AGU.  Excerpt: Earth’s future is bleak. At best, our planet will become a burned-out cinder as the Sun expands at the end of its life. At worst, it will be engulfed by the Sun, leaving no trace that it ever existed. Astronomers have found a clue as to which path Earth might follow in a star system about 4,300 light-years away. There, a rocky planet orbits the remains of a once Sun-like star at a distance similar to where Earth could park if it survives our own star’s death throes. The system “may offer a glimpse into the possible survival of planet Earth in the distant future,” according to  a new study  published in  Nature Astronomy . The system,  KMT-2020-BLG-0414L , was discovered in 2020 by the  Korea Microlensing Telescope Network , a set of three automated 1.6-meter telescopes in the Southern Hemisphere....  Full article at https://eos.org/articles/earth-may-survive-the-suns-demise . 

By Katrina Miller , The New York Times.  Excerpt: Before  the northern lights  fill the night sky on Earth with their eerie neon glow, a blast of electrified gas flares up from the sun’s surface. And scientists are now getting a powerful new view of how those ejections move through the corona, the sun’s tempestuous outer atmosphere. On Tuesday, the National Oceanic and Atmospheric Administration  unveiled the first imagery  from its newest telescope in space. Meteorologists will use pictures from the device to help them better forecast space weather, including when you can expect to see auroras. The new instrument is called the Compact Coronagraph, or CCOR-1. It launched in June aboard GOES-19, the newest of NOAA’s fleet of weather satellites. The coronagraph can continuously monitor the sun, and it will send data to scientists on the ground every 15 minutes. ...Earlier this month, NASA and NOAA  announced  that the sun had reached a peak in activity, which fluctuates in an 11-year cyc

By Douglas Fox , SciAm.  Excerpt: Sixty-six million years ago a 10-kilometer-wide space rock fell out of the sky over what is now the Yucatán Peninsula in the Gulf of Mexico. ...Yet the event’s infamous impactor was nothing compared with the asteroid that struck Earth 3.26 billion years ago, amid what scientists call the Archean eon of our planet’s 4.5-billion-year history. The Archean space rock in that impact, dubbed “S2,” was 50 to 200 times larger—big enough to blast at least 10,000 cubic kilometers of vaporized rock into the skies that then recondensed into molten droplets and rained back to Earth. Unsurprisingly, those circumstances would have been “really disastrous for early life,” says Nadja Drabon, a geologist at Harvard University. But her latest research suggests that—much like the more celebrated dino-killing space-rock impact—this vastly greater and more ancient collision also had an upside, giving Earth’s early biosphere a powerful boost. ...her scrutiny of rock layers i

By Kimberly M. S. Cartier , Eos/AGU.  Excerpt: Europa Clipper launched at 12:06 pm EDT on 14 October from NASA’s Kennedy Space Center in Florida. Clipper successfully deployed its solar panels and communicated with mission control once in space. ...NASA’s Europa Clipper spacecraft...will head to Jupiter’s icy moon Europa and determine whether it’s a hospitable place for life. ...There will be 49 flybys of Europa to study the moon from pole to pole ...The craft is set to  arrive  at Jupiter in April 2030. ...Europa is one of Jupiter’s four Galilean moons. Past missions to the Jovian system discovered that Europa, along with fellow icy moons Ganymede and Callisto, have vast liquid water oceans sloshing around beneath icy shells. “ Ocean worlds  have been considered potentially habitable environments for a while,” said  Monica Vidaurri , a doctoral student in planetary modeling at Stanford University in California. “This is the first time we’re really dedicating a spacecraft to [explorin