Collision Course? A Comet Heads for Mars
A comet is heading for Mars, and there is a chance that it might hit the Red Planet in October 2014. An impact wouldn't necessarily mean the end of NASA's Mars program. But it would transform the program along with Mars itself.
For a comet, visiting the sun is risky business. Fierce solar heat vaporizes gases long frozen in the fragile nucleus, breaking up some comets and completely destroying others.
Prime Time for PANSTARRS
This week is prime time for observing this comet. (Next opportunity, the year 108,013 +/- a few hundred or thousand years.)
What Exploded over Russia?
"It was a meteor strike--the most powerful since the Tunguska event of 1908," says Bill Cooke of NASA's Meteoroid Environment Office.
Possible Seismic Activity on Asteroid 2012 DA14
For eons, Earth has felt the tremors of asteroids striking our planet. From the extinction of the dinosaurs 65 million years ago to the felled forests around Tunguska in 1908, the space rocks keep coming. This week, Earth strikes back.