Showing posts from November, 2017

Recurring Martian Streaks: Flowing Sand, Not Water? Source:   By Jet Propulsion Laboratory News 2017-11-20.  . For GSS A Changing Cosmos chapter 7. Excerpt: Fast Facts: › Seasonal dark streaks on Mars have been described as possible signs of flowing water; a new study shows they are a better fit to dry flow processes. › The steepness of more than 150 of these features was assessed with a telescopic camera on a NASA Mars orbiter. › The findings add to evidence that these environments may be too dry for microbes to thrive, despite the presence of water in hydrated salts. › How seasonal warming triggers these streaks is still a puzzle, and water may be involved.... 

Nearby Earth-sized world may be the best candidate yet in the search for alien life Source:   By Loren Grush, The Verge Excerpt: ...Meet Ross 128 b, a newly discovered planet found orbiting around a small, faint star known as a red dwarf. The world, which is about one-and-a-half times the mass of Earth, may be in the star’s habitable zone, too. (That’s the spot where temperatures are just right, possibly allowing liquid water to pool on a planet’s surface.) Most exciting of all is that this planet is situated just 11 light-years away. That makes Ross 128 b the second closest potentially habitable exoplanet to Earth we know about after Proxima b, a rocky world that orbits around the nearest star to our Solar System, Proxima Centauri. However, Proxima Centauri isn’t a very “life-friendly” star. Also a red dwarf, frequently burps out intense, high-energy solar flares. ...But Ross 128 b’s star doesn’t seem to flare much at all. ...Ross 128 b is very close to its sun, in an orb