Cosmic Dust in Terrestrial Ice

For the last 30,000 years, our planet has been hit by a constant rain of cosmic dust particles. Two scientists from the Lamont-Doherty Earth Observatory (LDEO) at Columbia University in New York and the Alfred-Wegener-Institut (AWI) for Polar and Marine Research in Bremerhaven, Germany, have reached this conclusion after investigating the amount of the helium isotope 3He in cosmic dust particles preserved in an Antarctic ice core over the last 30,000 years. They have shown that this rare helium isotope in cosmic dust exceeds that of terrestrial dust in ice by a factor of 5,000. Moreover, measurements of the amount of 4He – a helium isotope much more common on Earth – in the Antarctic ice strongly suggest a change of origins in terrestrial dust between the last Ice Age and the interglacial warm period we currently live in.

http://www.awi-bremerhaven.de/AWI/Presse/PM/pm06-2.hj/060728Cosmic%20dust-e.html

Cosmic dust in ice cores sheds light on Earth's past climate

http://www.spaceref.com/news/viewpr.nl.html?pid=20483

Pre-life Molecules Are Present in Comets

"Evidence of atomic nitrogen in interstellar gas clouds suggests that pre-life
molecules may be present in comets, a discovery that gives a clue about the
early conditions that gave rise to life, according to researchers from the
University of Michigan and the Harvard-Smithsonian Center for Astrophysics."

http://www.spaceref.com/news/viewpr.nl.html?pid=20482