The "terminator" is the dividing line between day and night as seen from on high. This shadow line is diffuse and shows the gradual transition to darkness we experience as twilight. [more inside]
posted by nickyskye on Sep 16, 2008 - 44 comments

See Saturn this Saturday April 12 is the second annual International Sidewalk Astronomy Night, a worldwide event coordinated by the Sidewalk Astronomers. The group, founded in 1968 by John Dobson (subject of this documentary), is dedicated to a sort of guerrilla astronomy -- experienced stargeeks bringing their really good telescopes out to places where people are. So even on your way to the bars, the shows, and the honky-tonk you can see stuff like this and this - like these people did.
posted by Miko on Apr 10, 2008 - 16 comments

The AKARI mission has produced the first infra-red sky map in over 20 years.
posted by nthdegx on Jul 19, 2007 - 20 comments

Auroras have had many explanations throughout history. Now, science has answered many questions, thanks to spending a lot of time in Antarctica taking time-lapse films.
posted by MetaMonkey on Aug 15, 2006 - 14 comments

Sea And Sky:
Sea news, sky news, great photos, NASA Mission Insignia Patches (including Skylab), info about deep sea creatures, exploration timelines, and tonnes more.
posted by Fabulon7 on Nov 5, 2002 - 5 comments

northern-lights is a site dedicated to the Aurora Borealis- the science behind it, lights-spotting, forecasts and historical interpretations. If you live in North America and don't want to miss it, take advantage of the Aurora Alarm, thanks to Mark Haun and his skywatching friends.
posted by kahboom on Dec 27, 2001 - 4 comments