Wicked cool science

#1 The Aurora Borealis, or Northern Lights, is a naturally-occurring colorful display in the sky. In the upper atmosphere, a layer of charged particles discharged by the Sun are attached to the Earth's north and south magnetic poles. When the particles collide with molecules of oxygen and nitrogen in the air, they make the sky glow with bright colors. Using an enormous 960-kilowatt radio transmitter, researchers at the High Frequency Active Auroral Research Program (HAARP) facility near Gakona, Alaska created shiny "speckles" of light in the Aurora Borealis. "It's cool that they created a visible effect just using radio waves," says Pat Newell, who studies the aurorae at Johns Hopkins University. Link.

#2 According to Albert Einstein's general theory of relativity, gravity bends space and time. Picture the Earth resting at the bottom of a shallow cone, created by gravity, with moon rolling around the rim: this is similar to the way Einstein described gravity. In theory, As objects move throught he universe, they send out ripples of gravity, in other words, gravity waves.

Researchers at the Laser Interferometer Gravitational Wave Observatory (LIGO) hope to enlist up to a million personal computers, linked through the web, in their search for sources of the waves, which have long been predicted by Einstein but never directly observed. A system of lasers and mirrors collects data on gravitational disturbences. (Using computers all over the web to accomplish a single large task is also being done for climate change modeling. See previous post.) The computers will attempt to match the signals to waves of different frequencies. The database is so large that it will take a million active users to make a dent. The project, known as Einstein@home, will use the computer's idle time to search particular frequencies for a 'ringing' gravity wave source. While it's at work, the program also displays a screensaver charting the location of the search in the night sky. "It's really a cool kind of project," says Bruce Allen, a physicist at the University of Wisconsin at Milwaukee. Link.