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BLUE SKIES ON SATURN: Earth isn't the only planet with blue skies. Saturn has them, too, according to NASA's Cassini spacecraft. Get the full story from Science@NASA.

SOLAR FILAMENT: Today on the sun there's an enormous dark filament stretching 300,000+ miles from end to end--greater than the distance between Earth and the Moon. Experienced solar observers say it's one of the longest they've ever seen:

The filament on Feb. 19th. Photo credit: Greg Piepol.

Filaments are magnetic tubes suspended above the surface of the sun and filled with dense gas. Because the gas is cooler than the sun below it, filaments appear dark. Sometimes filaments erupt, producing a "Hyder flare." More often they don't. This one will probably persist for many days to come.

more images: from Ginger Mayfield of Divide, CO; from Didier Favre of Los Angeles, CA; from Andreas Murner of Lake Chiemsee, Bavaria, Germany.

GLORY! Air traveler Martin Baines was about to land at the airport in Oslo, Norway, on Feb. 14th when he looked out the window and saw this beautiful rainbow-colored ring around his airplane's shadow:

This is called a glory. Atmospheric optics expert Les Cowley explains:

"Water droplets in clouds are minuscule; some are 1000 times smaller than a raindrop. Light waves do not have enough room inside these tiny drops to form rainbows or cast sharp shadows. Instead, the waves are 'diffracted' into colorful shimmering rings; a corona around the sun and a glory directly opposite. Look for a glory when you fly. Although it appears to circle the airplane's shadow, it is actually circling yours--that is, where your shadow would be if you could see it."