domingo, 3 de abril de 2011

What's up in space? SATURN'S RINGS SURGE IN BRIGHTNESS [April 3rd]

SATURN'S RINGS SURGE IN BRIGHTNESS: 


This Sunday, April 3rd, Saturn will be "at opposition"--that is, opposite the sun in the skies of Earth. Whenever this happens, Saturn's rings surge in brightness. Why? Scroll down for the explanation; on the way, inspect this photo taken by Paul Haese of South Australia on March 30th:






"This is how Saturn looked through my 14-inch telescope," says Haese. "With opposition so close, the Seeliger effect is really starting to show itself. The rings are much more spectacular than in previous years."

The Seeliger effect, also known as the opposition effect, is what brightens the rings. Saturn's rings are made of frozen chunks ranging in size from dust to houses. Sunlight directly backscattered from those ice particles causes the ring system to shine even more than usual for a few days around opposition. The exact mechanism involves shadow-hiding and possibly coherent backscattering.

To find Saturn, go outside at midnight and look for a conspicuous yellow "star" in the constellation Virgo. Even a small telescope will show Saturn's brightening rings. [sky map]

More images: from Efrain Morales Rivera of Aguadilla, Puerto Rico; from Christopher Go of Cebu City, Philippines



Provided by Space Weather News