Anticrepuscular Rays over Colorado II
27.06.2016

What's happening over the horizon? Although the scene may appear somehow supernatural, nothing more unusual is occurring than a setting Sun and some well placed clouds. Pictured above are anticrepuscular rays. To understand them, start by picturing common crepuscular rays that are seen any time that sunlight pours though scattered clouds.

The Surface of Titan
20.08.2000

If sailing the hydrocarbon seas of Titan, beware of gasoline rain. Such might be a travel advisory issued one future day for adventurers visiting Titan, the largest moon of Saturn. New images of Titan's surface were released last week from the Canada-France Hawaii Telescope featuring the finest details yet resolved.

Eclipsed Moon and Stars
23.05.2003

Half-shadowed by the Earth, the Moon takes on a remarkable appearance against a field of stars in this intriguing telephoto picture recorded during a partial phase of last week's lunar eclipse. The picture is not a composite, but it has been digitally enhanced to bring out features covering a large range in brightness.

A Wolf-Rayet Star Blows Bubbles
3.01.1997

Wolf-Rayet stars can blow bubbles. These unusual stars are much hotter and more luminous than our Sun. All extremely massive stars will eventually evolve though a Wolf-Rayet phase. Approximately 200 Wolf-Rayet stars are known in our Milky Way Galaxy. Wolf-Rayet stars generate bubbles because they continually eject their outer atmosphere as a stellar wind.

Zodiacal Light and the False Dawn
16.01.2012

Is it dawn or false dawn? During certain times of the year, the horizon near the rising Sun will begin to glow unusually early. This early glow does not originate directly from the Sun, but rather from sunlight reflected by interplanetary dust.

A Solar Eclipse Quilt
13.11.2012

Some people are so inspired by solar eclipses that they quilt. Pictured above is a resulting textile from one such inspiration. The 38x38 inch quilt offers impressions of a total annular eclipse, when the Moon is too far from the Earth to cover the entire Sun, witnessed in Spain in October of 2005.

Space Shuttle Rising
24.05.2015

What's that rising from the clouds? The space shuttle. Sometimes, if you looked out the window of an airplane at just the right place and time, you could have seen something very unusual -- a space shuttle launching to orbit.

Plutos Sputnik Planum
22.11.2016

Is there an ocean below Sputnik Planum on Pluto? The unusually smooth 1000-km wide golden expanse, visible in the featured image from New Horizons, appears segmented into convection cells. But how was this region created?

Perseid Meteors over Turkey
1.08.2017

The Perseid Meteor Shower, usually the best meteor shower of the year, will peak late next week. A person watching a clear sky from a dark location might see a bright meteor every minute.

An Iridescent Cloud Over France
13.04.2004

Why would a cloud appear to be different colors? A relatively rare phenomenon known as iridescent clouds can show unusual colors vividly or a whole spectrum of colors simultaneously. These clouds are formed of small water droplets of nearly uniform size.