“The asteroid that impacted earth 65 million years ago killed off dinosaurs, but microalgae bounced back from the global extinction in about 100 years or less. Julio Sepúlveda, a geochemist at MIT, studied the molecular remains of microorganisms by extracting organic residues from rocks dated to the K-T extinction (in this research referred to as Cretaceous-Paleogene), and his results show that the ocean algae community greatly shrunk in size but only for about a century. ‘We found that primary production in this part of the ocean recovered extremely rapidly after the impact,’ says Julio Sepúlveda. Algae leave certain signatures of organic compounds and isotopes of carbon and nitrogen; bacteria leave different signatures. In the earliest layers after the asteroid impact, the researchers found much evidence for bacteria but little for algae, suggesting that right after the impact, algae production was greatly reduced. But the chemical signs of algae start to increase immediately above this layer. A full recovery of the ocean ecosystem probably took about a million years, but the quick rebound of photosynthesizing algae seems to confirm models that suggest the impact delivered a swift, abrupt blow to the Earth’s environment.”

DAWN WALTON

From Friday’s Globe and Mail

June 27, 2008 at 4:38 AM EDT

PRIDDIS, ALTA. — The space telescope will be no bigger than a hefty suitcase and weigh just 65 kilograms, but the Canadian scientists behind the project say when the device is launched two years from now, it may well go on to save the world.

The $12-million Near Earth Object Surveillance Satellite, dubbed NEOSSat, is considered a world’s first – designed specifically as an early warning system to pinpoint asteroids on a collision course with Earth. It will also detect space junk in the path of other orbiting satellites to prevent crashes that could shut down telecommunications – television, telephone, GPS and banking systems – around the globe.

http://www.sott.net/articles/show/129699-The-Hope

Smaller asteroids may pose greater danger than previously believed

ALBUQUERQUE, N.M. — The stunning amount of forest devastation at Tunguska a century ago in Siberia may have been caused by an asteroid only a fraction as large as previously published estimates, Sandia National Laboratories supercomputer simulations suggest.

“The asteroid that caused the extensive damage was much smaller than we had thought,” says Sandia principal investigator Mark Boslough of the impact that occurred June 30, 1908. “That such a small object can do this kind of destruction suggests that smaller asteroids are something to consider. Their smaller size indicates such collisions are not as improbable as we had believed.”

Carl Sagan

“Right now the U.S. doesn’t h