Scientific American 12 Jun 2019, 18:00 UTC The sea sloshing beneath the icy surface of Jupiter’s moon Europa just might be the best incubator for extraterrestrial life in our solar system, but it is concealed by the moon’s frozen outer shell—presenting a challenge for astrobiologists. Luckily they can catch a partial glimpse by analyzing the flavor of the surface. And the results are salty.
Scientific American 12 Jun 2019, 16:15 UTC Once a water-rich Eden, the hellish planet could reveal how to find habitable worlds around distant stars
Centauri Dreams 12 Jun 2019, 16:00 UTC We’re on the cusp of exciting developments in exoplanet detection, as yesterday’s post about the Near Earths in the AlphaCen Region (NEAR) effort makes clear. Adapting and extending the VISIR instrument at the European Southern Observatory’s Very Large Telescope in Chile, NEAR has seen first light and wrapped up its first observing run of Centauri A and B. What it finds should have interesting ramifications, for its infrared detection capabilities won’t find anything smaller than twice the size of Earth, meaning a habitable zone discovery might rule out a smaller, more Earth-like world, while a null result leaves that possibility open.
Starts With a Bang! 12 Jun 2019, 14:01 UTC Somewhere, far away, if you believe what you read, there’s a hole in the Universe. There’s a region of space so large and empty, a billion light-years across, that there’s nothing in it at all. There’s no matter of any type, normal or dark, and no stars, galaxies, plasma, gas, dust, black holes, or anything else. There’s no radiation in there at all, either. It’s an example of truly empty space, and its existence has been visually captured by our greatest telescopes. At least, that’s what some people are saying, in a photographic meme that’s been spreading around the internet for years and refuses to die. Scientifically, though, there’s nothing true about these assertions at all. There is no hole in the Universe; the closest we have are the underdense regions known as cosmic voids, which still contain matter. Moreover, this image isn’t a void or hole at all, but a cloud of gas. Let’s do the detective work to show you what’s really going on.
Bad Astronomy 12 Jun 2019, 13:00 UTC Some big news from Galaxy Zoo: It's looking very much like a classic classification scheme for galaxies — first dreamed up by Edwin Hubble himself! — may be, um, wrong. The consequences of this are as dramatic as they are cosmic: It implies very strongly that the way we've been thinking about how galaxies form and maintain spiral arms is also wrong. Instead of being semi-permanent features of galaxies, they may instead actually wind themselves up, disappear, and reform again! Wow. This is a very big deal.
SciTech Daily 12 Jun 2019, 01:43 UTC The Solar System’s second largest planet both in mass and size, Saturn is best known for its rings. These are divided by a wide band, the Cassini Division, whose formation was poorly understood until very recently. Now, researchers from the CNRS, the Paris Observatory – PSL and the University of Franche-Comté have shown that Mimas, one of Saturn’s moons, acted as a kind of remote snowplough, pushing apart the ice particles that make up the rings.
That Explains a Lot. The Moon’s Largest Crater has a Chunk of Metal Embedded in it That’s 5 Times Bigger than the Big Island of Hawaii11 Jun 2019, 20:25 UTC One of the largest craters in the Solar System is on our Moon. It’s called the South Pole-Aitken (SPA) basin and it’s 2,500 km (1,600 mi) in diameter and 13 km (8.1 mi) deep. A new study says that the basin may contain an enormous chunk of metal that’s larger than Hawaii’s Big Island.
NASA Space Station Blog 11 Jun 2019, 16:23 UTC Four Expedition 59 astronauts underwent periodic health checkups and regularly scheduled eye scans today. The International Space Station residents also had time set aside for space gardening, furnace work, crew ship packing and radiation checks.
Starts With a Bang! 11 Jun 2019, 14:01 UTC At a fundamental level, what is our Universe made of? This question has driven physics forward for centuries. Even with all the advances we’ve made, we still don’t know it all. While the Large Hadron Collider discovered the Higgs boson and completed the Standard Model earlier this decade, the full suite of the particles we know of only make up 5% of the total energy in the Universe. We don’t know what dark matter is, but the indirect evidence for it is overwhelming. Same deal with dark energy. Or questions like why the fundamental particles have the masses they do, or why neutrinos aren’t massless, or why our Universe is made of matter and not antimatter. Our current tools and searches have not answered these great existential puzzles of modern physics. Particle physics now faces an incredible dilemma: try harder, or give up.