Astro Blog

https://www.nature.com/articles/d41586-023-03271-4 By Alexandra Witze , Nature.  Excerpt: A meteorite that slammed into Mars in September 2021 has rewritten what scientists know about the planet’s interior. By analysing the seismic energy that vibrated through the planet after the impact, researchers have discovered a layer of molten rock that envelops Mars’s liquid-metal core. The finding, reported today in two papers in  Nature 1 , 2 , means that the Martian core is smaller than previously thought. It also resolves some lingering questions about how the red planet formed and evolved over billions of years. The discovery comes from NASA’s InSight mission,  which landed a craft with a seismometer on Mars’s surface . Between 2018 and 2022, that instrument  detected hundreds of ‘marsquakes’ shaking the planet . Seismic waves produced by quakes or impacts can slow down or speed up depending on what types of material they are travelling through, so seismologists can measure the waves’ pass

https://news.berkeley.edu/2023/10/19/webb-telescope-discovers-intense-jet-stream-in-jupiters-atmosphere By Robert Sanders , UC Berkeley News. Excerpt: NASA’s James Webb Space Telescope has discovered a fast-moving jet stream in Jupiter’s atmosphere that is blowing twice as fast as the visible cloud layers below it, creating wind shears that far exceed anything seen on Earth. The high-speed jet stream, which is traveling at 320 miles per hour (515 kilometers per hour) and is more than 3,000 miles (4,800 kilometers) wide, sits over Jupiter’s equator, 15 to 30 miles (25 to 50 kilometers) above the main cloud deck familiar from optical photos. ...winds in the visible cloud layer blow at about 180 mph (250 km/hour). This means that for every kilometer above these visible clouds, the wind speed increases by 7 to 10 kilometers per hour, according to Ricardo Hueso, lead author of a paper describing the findings published today in the journal  Nature Astronomy ....

https://www.science.org/doi/10.1126/science.adi4639 By ANDREW FALLE ,  EWAN WRIGHT ,  AARON BOLEY , AND  MICHAEL BYERS , Science.  Abstract: The occupation of Earth orbits by large constellations of satellites has received considerable attention in recent years. About 4500 Starlink and 630 OneWeb satellites are on orbit as of July 2023 ( 1 ), but this is only the beginning. Recent filings for radio spectrum with the International Telecommunication Union (ITU) suggest that a dramatic increase in satellite numbers is possible, much more than the tens of thousands often reported. Constellations much larger than SpaceX’s Starlink have been filed, including a 337,320-satellite constellation named Cinnamon-937 that was filed in September 2021. By treating orbital space as an unlimited resource, humanity is creating serious safety and longterm sustainability challenges to the use of low Earth orbit (LEO), including science conducted from space and the ground. The ITU filings are the warning,

https://www.bbc.com/news/science-environment-66974738 By Jonathan Amos , The Guardian.  Excerpt: Jupiter-sized "planets" free-floating in space, unconnected to any star, have been spotted by the James Webb Space Telescope (JWST). What's intriguing about the discovery is that these objects appear to be moving in pairs. Astronomers are currently struggling to explain them. The telescope observed about 40 pairs in a fabulously detailed new survey of the famous Orion Nebula. They've been nicknamed Jupiter Mass Binary Objects, or "JuMBOs" for short. ..."Gas physics suggests you shouldn't be able to make objects with the mass of Jupiter on their own, and we know single planets can get kicked out from star systems. But how do you kick out pairs of these things together? Right now, we don't have an answer. It's one for the theoreticians," the European Space Agency's (Esa) senior science adviser told BBC News.... 

https://www.nytimes.com/2023/10/01/realestate/nasa-homes-moon-3-d-printing.html By Debra Kamin , The New York Times.  Excerpt: ...NASA is going to build houses on the moon — ones that can be used not just by astronauts but ordinary civilians as well. They believe that by 2040, Americans will have their first subdivision in space. Living on Mars isn’t far behind. Some in the scientific community say NASA’s timeline is overly ambitious, particularly before a proven success with a new lunar landing. But seven NASA scientists interviewed for this article all said that a 2040 goal for lunar structures is attainable if the agency can continue to hit their benchmarks. The U.S. space agency will blast a 3-D printer up to the moon and then build structures, layer by additive layer, out of a specialized lunar concrete created from the rock chips, mineral fragments and dust that sits on the top layer of the moon’s cratered surface and billows in poisonous clouds whenever disturbed — a moonshot of