Asteroid impacts were a hazard to any life on the Hadean Earth. A traditional approach to geochemical models of the asteroid impactors uses the concentration of highly siderophile elements including the Pt-group in the silicate Earth. These elements occur in roughly chondritic relative ratios, but with absolute concentrations <1% chondrite. This veneer component implies addition of chondrite-like material with 0.3-0.7% mass of the Earth’s mantle or an equivalent planet-wide thickness of 5-20 km. The veneer thickness, 200-300 m, within the lunar crust and mantle is much less.
History of Clays on Mars: How We Found Them and Why They are Important for Astrobiology
A SPACE ODYSSEY ABOVE AND BELOW GROUND
International Space Orchestra + Sigur Rós
24th SEPTEMBER 2016
Talk to Me I Am A Space Viking// Interval event
Sigur Rós interval as announced from the stage. interval (10 mins)
ENCORE Are you skeptical? Sure, you raise an eyebrow when some Nigerian prince asks for your bank numbers, or when a breakfast cereal claims that it will turn your kid into a professional athlete overnight.
With the fall breezes beginning their appearances here in Mountain View, our Summer Interns have gone back to school after impressing us with their summer projects. However, SETI Institute scientists are still keeping busy. They continue to unravel more puzzles about our local celestial neighbors as well as other worlds many light-years away. Every day, researchers at the SETI Institute are expanding both our knowledge and understanding in the quest to find life beyond Earth.
Image screenshot taken from the American Meteor Society website.
SETI Institute astronomer Peter Jenniskens notes that a very bright meteor, a so-called fireball, was seen in the vicinity of the Allen Telescope Array on Thursday, September 15 at about 7:48 pm local time.
You can read the report here:http://www.amsmeteors.org/members/imo_view/event/2016/3440
Birds do it, bees do it, but humans may not
How commonplace is life? In particular, are worlds where biology can gain a foothold very common or distressingly rare?
John D. Rummel