Sun and Winter Solstice 1996
20.12.1996

Today is the Winter Solstice for 1996. After steadily sinking in Northern Hemisphere skies, the Sun is now at its lowest declination - marking the first day of Northern Winter (but Southern Summer!). The Earth...

M100 and the Expanding Universe
8.01.1996

The distance to the swirling grand design spiral M100 is causing quite a stir among astronomers. Many believe that the Hubble Space Telescope's recent distance measurement to this galaxy accurately calibrates the expansion rate of the universe. Others believe this distance measurement is misleading.

Searching for Meteorites in Antarctica
25.12.2002

Where is the best place on Earth to find meteorites? Although meteors fall all over the world, they usually just sink to the bottom of an ocean, are buried by shifting terrain, or are easily confused with terrestrial rocks.

Anticrepuscular Rays Over Horseshoe Canyon
25.02.2003

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.

Trifid Pillars and Jets
27.12.2003

Dust pillars are like interstellar mountains. They survive because they are more dense than their surroundings, but they are being slowly eroded away by a hostile environment. Visible in the above picture...

Mammatus Clouds Over Mexico
7.06.2004

When do cloud bottoms appear like bubbles? Normal cloud bottoms are flat because moist warm air that rises and cools will condense into water droplets at a very specific temperature, which usually corresponds to a very specific height. After water droplets form that air becomes an opaque cloud.

Genesis Missions Hard Impact
14.09.2004

A flying saucer from outer space crash-landed in the Utah desert last week after being tracked by radar and chased by helicopters. No space aliens were involved, however. The saucer, pictured above...

The Inner Coma of Comet Holmes
12.11.2007

What's happening to Comet Holmes? The rare comet remains visible to the unaided eyes of northern observers as an unusual small puff ball in the constellation of Perseus. A high resolution set of images of the comet's inner coma, taken last week and shown above, reveals significant detail.

Comet McNaught Over Chile
19.01.2008

Comet McNaught was perhaps the most photogenic comet of our time. After making quite a show in the northern hemisphere in early January, the comet moved south and developed a long and unusual dust tail that dazzled southern hemisphere observers. In this image, Comet McNaught was captured one year ago above Chile.

Seaside Moon Mirage
20.06.2009

This surprising view of the Full Moon rising on June 7 was captured with a telephoto lens from a seaside balcony near Nice, France. The orange Moon's dark markings and odd shape put the photographer in mind of an alien creature's face staring down at the passing ship.