Four Billion BCE: Battered Earth
5.08.2014

No place on Earth was safe. Four billion years ago, during the Hadean eon, our Solar System was a dangerous shooting gallery of large and dangerous rocks and ice chunks. Recent examination of lunar...

NGC 6302: Big Bright Bug Nebula
5.05.2004

The bright clusters and nebulae of planet Earth's night sky are often named for flowers or insects, and NGC 6302 is no exception. With an estimated surface temperature of about 250,000 degrees...

The Snows of Churyumov Gerasimenko
14.03.2020

You couldn't really be caught in this blizzard while standing by a cliff on Churyumov-Gerasimenko. Orbiting the comet -- frequently abbreviated as 67P or CG -- in June of 2016, the Rosetta spacecraft's narrow...

Comet LINEAR Disperses
8.08.2000

What's happened to the nucleus of Comet LINEAR? The brightest comet this year has unexpectedly broken up into many smaller pieces. The break-up occurred on or about July 25 and was noted by many astronomers around the world with particularly pioneering work by Mark Kidger (IAC).

Close Up of Enceladus Tiger Stripes
31.03.2008

Could life exist beneath Enceladus? A recent flyby of Saturn's icy moon has bolstered this fascinating idea. Two years ago, images from the robotic Cassini spacecraft orbiting Saturn led astronomers to the undeniable...

In Through and Beyond Saturns Rings
26.10.2011

A fourth moon is visible on the above image if you look hard enough. First -- and furthest in the background -- is Titan, the largest moon of Saturn and one of the larger moons in the Solar System. The dark feature across the top of this perpetually cloudy world is the north polar hood.

Enceladus Backlit by Saturn
8.02.2012

This moon is shining by the light of its planet. Specifically, a large portion of Enceladus pictured above is illuminated primarily by sunlight first reflected from the planet Saturn. The result is that the normally snow-white moon appears in the gold color of Saturn's cloud tops.

Frosted Leaf Orion
16.11.2010

Sometimes, you can put some night sky in your art. Captured above Japan earlier this month, a picturesque night sky was photographed behind a picturesque frosted leaf. The reflecting ice crystals on the leaf coolly mimic the shining stars far in the background.

APOD: 2025 January 28 Б Comet G3 ATLAS over Uruguay
27.01.2025

Comets can be huge. When far from the Sun, a comet's size usually refers to its hard nucleus of ice and rock, which typically spans a few kilometers -- smaller than even a small moon.

Circular Sun Halo
9.06.2021

Want to see a ring around the Sun? It's easy to do in daytime skies around the world. Created by randomly oriented ice crystals in thin high cirrus clouds, circular 22 degree halos are visible much more often than rainbows. This one was captured by smart phone photography on May 29 near Rome, Italy.