Physics World Blog
Machine-learning study of metallic hydrogen provides clues about Jupiter’s interior - Astronomy and space – Physics World22 Sep 2020, 15:59 UTC Deep within the interiors of gas-giant planets like Jupiter, materials can be subjected to millions of atmospheres of pressure. In the most extreme conditions, even hydrogen no longer exists in its usual molecular form. Instead, its covalent bonds break down and the material is believed to become a metallic solid. As astronomers seek to understand the physical structures of gas giants, a detailed knowledge of this metallization process is crucial.
Sky and Telescope 22 Sep 2020, 09:19 UTC There comes a time in every star’s evolution when the hydrogen in their cores runs out. This explosive midlife crisis is disruptive to local planetary systems, obliterating inner worlds and tossing outer ones into the void of deep space. When our own Sun expands into a red giant and then collapses into a white dwarf, Mercury, Venus, and perhaps even Earth will be destroyed. Observations of white dwarf systems show the celestial wreckage such dying stars leave behind: massive debris fields and planets literally ripped to pieces.
Centauri Dreams 21 Sep 2020, 15:26 UTC So often a discovery sets off a follow-up study that strikes me as even more significant in practical terms. This is not for a moment to downplay the accomplishment of Andrew Vanderburg (University of Wisconsin – Madison) and team that discovered a planet in close orbit around a white dwarf. This is the first time we’ve found a planet that has survived its star’s red giant phase and remains in orbit around the remnant, and quite a tight orbit at that. Previously, we’ve had good evidence only of atmospheric pollution in such stars, indicating infalling material from possible asteroids or other objects during the primary’s cataclysmic re-configuration.
Parabolic Arc 21 Sep 2020, 14:30 UTC SAN FRANCISCO (Breakthrough Initiatives PR) – Breakthrough Initiatives, the privately-funded space science programs founded by science and technology investor and philanthropist Yuri Milner, are funding a research study into the possibility of primitive life in the clouds of Venus. The study is inspired by the discovery, announced yesterday, of the gas phosphine, considered a potential biosignature, in the planet’s atmosphere.
Universe Today 21 Sep 2020, 03:11 UTC Last week, an incredible announcement was made about the search for extraterrestrial life: Phosphine gas detected in the clouds of Venus – a potential indicator of life or “biosignature.” Now some gases might be a false positive for biosignatures because they can be created by other chemical processes on a planet like photochemical processes in the atmosphere or geological processes beneath the surface that create a given gas. For example, methane can also be a biosignature, and we’ve been hunting it down on Mars, but we know that methane can also be created geologically. Finding phosphine in Venusian clouds is truly remarkable because we don’t presently know of any way to create phosphine abiotically or without life being a part of the equation. Question is – how much life??
SciTech Daily 21 Sep 2020, 02:16 UTC A Southwest Research Institute scientist has identified stellar phosphorus as a probable marker in narrowing the search for life in the cosmos. She has developed techniques to identify stars likely to host exoplanets, based on the composition of stars known to have planets, and proposes that upcoming studies target stellar phosphorus to find systems with the greatest probability for hosting life as we know it.
Starts With a Bang! 18 Sep 2020, 14:01 UTC There are only 3 populations of stars, but “generations” is a more complex question.
Universe Today 18 Sep 2020, 09:51 UTC Can the galaxy’s dead stars help us in our search for life? A group of researchers from Cornell University thinks so. They say that watching exoplanets transit in front of white dwarfs can tell us a lot about those planets. It might even reveal signs of life.
astrobites 17 Sep 2020, 16:01 UTC There are lots of stars out there in the Universe, and a large chunk of those are M dwarfs. These are the smallest and reddest stars, coming last in the sequence of spectral types (O, B, A, F, G, K, and last but not least: M). Bonus: since they’re so small and dim, it actually makes it easier to find smaller, terrestrial planets around them! Given that they’re so plentiful and we have a good shot at peering into their habitable zones, it makes sense that we’d want to think about what life on a planet around a M dwarf would be like.
Universe Today 17 Sep 2020, 02:53 UTC The discovery of phosphine in the upper clouds in Venus’ atmosphere has generated a lot of excitement. On Earth, phosphine is produced biologically, so it’s a sign of life. If it’s not produced by life, it takes an enormous amount of energy to be created abiologically.