Relax with Nature

Wednesday, April 27, 2011

Monday, February 14, 2011

Three dimesion glory of the Sun

NASA's twin STEREO probes beam back photos of entire sun.

NASA's twin STEREO probes were positioned on each side of the sun on Sunday and are now beaming back uninterrupted images of the entire star — front and back.

"For the first time ever, we can watch solar activity in its full 3-dimensional glory," says Angelos Vourlidas, a member of the STEREO science team at the Naval Research Lab in Washington, DC.

NASA released a 'first light' 3D movie on, naturally, Super Bowl Sunday.

Vourlidas called it a "big moment in solar physics."

"STEREO has revealed the sun as it really is--a sphere of hot plasma and intricately woven magnetic fields," he said.

"There are many fundamental puzzles underlying solar activity. By monitoring the whole sun, we can find missing pieces."

Each STEREO -- Solar TErrestrial RElations Observatory -- probe photographs half of the star and beams the images to Earth, where researchers combine the two views to create a sphere.

But these are no ordinary pictures.

STEREO's telescopes are tuned to four wavelengths of extreme ultraviolet radiation selected to trace key aspects of solar activity such as flares, tsunamis and magnetic filaments. Nothing escapes their attention.

"With data like these, we can fly around the sun to see what's happening over the horizon — without ever leaving our desks," says STEREO program scientist Lika Guhathakurta at NASA headquarters.

"I expect great advances in theoretical solar physics and space weather forecasting."

"With this nice global model, we can now track solar storms heading toward other planets, too," Guhathakurta noted. "This is important for NASA missions to Mercury, Mars, asteroids … you name it."

In the past, an active sunspot could emerge on the far side of the sun completely hidden from Earth. The sun's rotation could then turn that region toward our planet, spitting flares and clouds of plasma, with little warning.

"Not anymore," says Bill Murtagh, a senior forecaster at NOAA's Space Weather Prediction Center in Boulder, Col.

"Farside active regions can no longer take us by surprise. Thanks to STEREO, we know they're coming."

Researchers say these first-look whole sun images are just a hint of what's to come and movies with even higher resolution and more action will be released in the days and weeks ahead as more data are processed