Ice Halos by Moonlight
13.05.2022

An almost full moon on April 15 brought these luminous apparitions to a northern spring night over Alberta Canada. On that night, bright moonlight refracted and reflected by hexagonal ice crystals in high clouds created a complex of halos and arcs more commonly seen by sunlight in daytime skies.

Tails Of Comet LINEAR
27.07.2000

Comet C/1999 S4 LINEAR is only one of many comets discovered with the Lincoln Near Earth Asteroid Research (LINEAR) telescope operating near Soccoro, New Mexico, USA. Traveling steadily southward through Earth's night...

Island Universe, Cosmic Sand
23.08.2002

On August 13, while counting Perseid meteors under dark, early morning Arizona skies, Rick Scott set out to photograph their fleeting but fiery trails. The equipment he used included a telephoto lens and fast color film. After 21 pictures he'd caught only two meteors, but luckily this was one of them.

X-Rays from the Galactic Core
5.11.2004

Using the orbiting Chandra X-ray Observatory, astronomers have taken this long look at the core of our Milky Way galaxy, some 26,000 light-years away. The spectacular false-color view spans about 130 light-years.

M27: Not A Comet
3.08.2006

While searching the skies above 18th century France for comets, astronomer Charles Messier diligently recorded this object as number 27 on his list of things which are definitely not comets. So what is it?

Seasonal Dark Streaks on Mars
8.08.2011

What is causing these dark streaks on Mars? A leading hypothesis is flowing -- but quickly evaporating -- water. The streaks, visible in dark brown near the image center, appear in the Martian spring and summer but fade in the winter months, only to reappear again the next summer.

NGC 602 and Beyond
1.04.2017

Near the outskirts of the Small Magellanic Cloud, a satellite galaxy some 200 thousand light-years distant, lies 5 million year young star cluster NGC 602. Surrounded by natal gas and dust...

Tychos Supernova Remnant in Xray
12.01.2019

What star created this huge puffball? What's pictured is the hot expanding nebula of Tycho's supernova remnant, the result of a stellar explosion first recorded over 400 years ago by the famous astronomer Tycho Brahe. The featured image is a composite of three X-ray colors taken by the orbiting Chandra X-ray Observatory.

Evidence of an Active Volcano on Venus
13.01.2020

Are volcanoes still active on Venus? More volcanoes are known on Venus than Earth, but when Venusian volcanoes last erupted is not directly known. Evidence bolstering very recent volcanism on Venus has recently been uncovered, though, right here on Earth.

APOD: 2020 August 2 Б Two Worlds One Sun
1.08.2020

How different does sunset appear from Mars than from Earth? For comparison, two images of our common star were taken at sunset, one from Earth and one from Mars. These images were scaled to have same angular width and featured here side-by-side.