Bow Tie Moon and Star Trails
8.02.2018

On January 31, a leisurely lunar eclipse was enjoyed from all over the night side of planet Earth, the first of three consecutive total eclipses of the Moon. This dramatic time-lapse image followed the celestial performance for over three hours in a combined series of exposures from Hebei Province in Northern China.

APOD: 2024 October 14 Б Comet Tsuchinshan ATLAS Over the Lincoln Memorial
14.10.2024

Go outside at sunset tonight and see a comet! C/2023 A3 (TsuchinshanБATLAS) has become visible in the early evening sky in northern locations to the unaided eye. To see the comet, look west through a sky with a low horizon.

APOD: 2025 July 11 Б The Veins of Heaven
11.07.2025

Transfusing sunlight as the sky grew darker, this exceptional display of noctilucent clouds was captured on July 10, reflected in the calm waters of Vallentuna Lake near Stockholm, Sweden. From the edge of space...

GL 229B: An Elusive Brown Dwarf?
4.12.1995

What type of matter makes up most of the universe? This question is arguably the most perplexing astronomical mystery of our time. A leading candidate is a type of dim, low mass star called a "brown dwarf" star.

Grey Sun Seething
8.01.1997

The Sun's surface is not smooth. It has thousands of bumps called granules and usually a few dark depressions called sunspots. Each of the numerous granules is the size of an Earth continent, but much shorter lived.

Heaven on Earth
23.02.2004

If sometimes it appears that the entire Milky Way Galaxy is raining down on your head, do not despair. It happens twice a day. As the Sun rises in the East, wonders of the night sky become less bright than the sunlight scattered by our own Earth's atmosphere, and so fade from view.

IC 410 and NGC 1893
15.08.2006

A faint, dusty rose of the northern sky, emission nebula IC 410 lies about 12,000 light-years away in the constellation Auriga. The cloud of glowing hydrogen gas is over 100 light-years across, sculpted by stellar winds and radiation from embedded open star cluster NGC 1893.

Sand Dunes Thawing on Mars
3.03.2008

What are these strange shapes on Mars? Defrosting sand dunes. As spring now dawns on the Northern Hemisphere of Mars, dunes of sand near the pole, as pictured above, are beginning to thaw. The carbon dioxide and water ice actually sublime in the thin atmosphere directly to gas.

White Rock Fingers on Mars
30.10.2011

What caused this unusual light rock formation on Mars? Intrigued by the possibility that they could be lakebed dried-up, detailed studies of these fingers now indicate a more mundane possibility: volcanic ash. Studying the exact color of the formation indicated the possible volcanic origin.

Ghost of the Cepheus Flare
31.10.2011

Spooky shapes seem to haunt this starry expanse, drifting through the night in the royal constellation Cepheus. Of course, the shapes are cosmic dust clouds faintly visible in dimly reflected starlight. Far from your...