More via the European Space Agency:
Eberswalde crater contains a rare case of a martian delta. Channels which fed the lake in the crater are very well preserved. The delta deposits and channels together provide a clear indication of liquid surface water during the early history of Mars.
Credits: ESA/DLR/FU Berlin (G. Neukum)
This image, via APOD, was constructed by sandwiching two night skies, showing the Milky Way, from two different locations — one from each hemisphere.
More via APOD:
Explanation: A quest to find planet Earth’s darkest night skies led to this intriguing panorama. In projection, the mosaic view sandwiches the horizons visible in all-sky images taken from the northern hemisphere’s Canary Island of La Palma (top) and the south’s high Atacama Desert between the two hemispheres of the Milky Way Galaxy. The photographers’ choice of locations offered locally dark skies enjoyed by La Palma’s Roque de los Muchachos Observatory and Paranal Observatory in Chile. But it also allowed the directions to the Milky Way’s north and south galactic poles to be placed near the local zenith. That constrained the faint, diffuse glow of the plane of the Milky Way to the mountainous horizons. As a result, an even fainter S-shaped band of light, sunlight scattered by dust along the solar system’s ecliptic plane, can be completely traced through both northern and southern hemisphere night skies.
Voyager 1 and Voyager 2 are about to pierce the heleosphere, which protects our solar system from cosmic radiation, and enter interstellar space. The probes have already collected a wealth of data about our solar system, and they’re now collecting data about the edge of our solar system and soon, they’ll collect data about what lies beyond our solar system.
In addition to collecting information about our solar system and what lies beyond, each probe also contains a special record that contains information about our planet and humanity. Via NASA:
Each probe is famously equipped with a Golden Record, literally, a gold-coated copper phonograph record. It contains 118 photographs of Earth; 90 minutes of the world’s greatest music; an audio essay entitled Sounds of Earth (featuring everything from burbling mud pots to barking dogs to a roaring Saturn 5 liftoff); greetings in 55 human languages and one whale language; the brain waves of a young woman in love; and salutations from the Secretary General of the United Nations. A team led by Carl Sagan assembled the record as a message to possible extraterrestrial civilizations that might encounter the spacecraft.
“A billion years from now, when everything on Earth we’ve ever made has crumbled into dust, when the continents have changed beyond recognition and our species is unimaginably altered or extinct, the Voyager record will speak for us,” wrote Carl Sagan and Ann Druyan in an introduction to a CD version of the record.
Image: Recently, one of Saturn’s moons — Rhea — was discovered to have “an atmosphere of oxygen and carbon dioxide.” Image via NASA/JPL/Space Science Institute.
Has NASA discovered extraterrestrial life? My guess is probably not. On Thursday, NASA will “discuss an astrobiology finding that will impact the search for evidence of extraterrestrial life“. To me, the press release reads like the announcement of a discovery or a new method that will improve or expand the chances of scientists finding extraterrestrial life.
Jason Kottke of kottke.org speculates that NASA has “discovered arsenic on Titan and maybe even detected chemical evidence of bacteria utilizing it for photosynthesis.” Phil Plait of Bad Astronomy is skeptical that exterrestrial life has been discovered and notes that the discovery is “most likely going to be something about conditions on another moon or planet conducive for life.” NASA’s news conference is scheduled for 2 p.m. EST on Thursday, Dec. 2.
