NASA has awarded the University of California, Berkeley, a $173 million contract to build and operate a fleet of five satellites to pinpoint the event in Earth’s magnetic neighborhood that triggers violent but colorful eruptions in the Northern and Southern lights. The aurora borealis and aurora australis are shimmering light shows that brighten the polar nights, generated by showers of electrons descending along magnetic field lines onto the poles. These high-speed electrons spark colored lights as they hit the atmosphere, much like a color TV lights up when an electron beam hits the phosphorescent screen.
The idea that even small asteroids can create hazardous tsunamis may at last be pretty well washed up. Small asteroids do not make great ocean waves that will devastate coastal areas for miles inland, according to both a recently released 1968 U.S. Naval Research report on explosion-generated tsunamis and terrestrial evidence. University of Arizona planetary scientist H. Jay Melosh is talking about it today at the 34th annual Lunar and Planetary Science Conference in League City, Texas. His talk, “Impact-Generated Tsunamis: an Over-Rated Hazard,” is part of the session, “Poking Holes: Terrestrial Impacts.”