McCool Hill on Mars
15.03.2006

You can make it. Winter is rapidly advancing on the southern hemisphere on Mars, and the lack of sunlight could be dangerous unless you find a good place to hibernate. There it is ahead: McCool Hill.

Vega
15.07.1997

Vega is a bright blue star 25 light years away. Vega is the brightest star in the Summer Triangle, a group of stars easily visible summer evenings in the northern hemisphere. The name Vega...

Annular Eclipse Over Myanmar
26.01.2010

A hole crossed the Sun for a few minutes this month, as seen across a thin swath of planet Earth. The event on January 15 was actually an annular solar eclipse, and the hole was really Earth's Moon, an object whose dark half may appear even darker when compared to the tremendously bright Sun.

A RADARSAT Map of Antarctica
16.11.1999

It's not easy to make a map of Antarctica. Earth's southern most continent is so cold and inhospitable that much of it remains unexplored. From space, though, it is possible to map this entire region by radar: by systematically noting how long it takes for radio waves to reflect off the terrain.

Perigee s Full Moon
22.06.2013

A big, bright, beautiful Full Moon will rise at sunset on Sunday. Its exact full phase (June 23, 11:32 UT) will occur shortly before it reaches perigee, the closest point to Earth in the Moon's orbit, and make it the largest Full Moon of 2013. But such circumstances are not very rare.

Mars Rises above the Lunar Limb
9.12.2022

On the night of December 7 Mars wandered near the Full Moon. In fact the Red Planet was occulted, passing behind the Moon, when viewed from locations across Europe and North America. About...

Ptolemaeus, Alphonsus and Arzachel
9.02.2007

These three ancient, large impact craters lie on the north eastern shores of Mare Nubium, the lunar Sea of Clouds. Along the top of the stark mosaic (left to right) are the namesakes of Ptolemaeus, Alphonsus and Arzachel.

White Rock Fingers on Mars
15.02.2016

What caused this unusual light rock formation on Mars? Intrigued by the possibility that they could be salt deposits left over as an ancient 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.

Messier 2
4.04.2019

After the Crab Nebula, M1, this giant star cluster is the second entry in 18th century astronomer Charles Messier's famous list of things with are not comets. M2 is one of the largest globular star clusters now known to roam the halo of our Milky Way galaxy.

APOD: 2026 February 22 Б Shadow of a Martian Robot
22.02.2026

What if you saw your shadow on Mars and it wasn't human? Then you might be the Opportunity rover exploring Mars. Opportunity explored the Red Planet from 2004 to 2018, finding evidence of ancient water, and sending breathtaking images across the inner Solar System.