Phobos Over Mars
12.03.1999

Hurtling through space a mere 3,000 miles above the Martian surface, the diminutive moon Phobos (below and left of center) was imaged against the backdrop of a large shield volcano by the Viking 2 Orbiter in 1977.

ASCA X-Ray Observatory
19.02.1996

Today marks the third anniversary of the launch of the Advanced Satellite for Cosmology and Astrophysics (ASCA; renamed from Astro D when launched). ASCA, seen here superposed on galaxy M31, is a Japanese satellite for which NASA has provided some scientific equipment. ASCA carries four large-area X-ray telescopes.

The Frothy Milky Way
9.10.1999

Astronomers have discovered that looking at dust along the plane of our Milky Way Galaxy is a bit like looking into a frothy glass of beer. The dust between stars in our galaxy appears...

Infrared Saturn
24.07.1999

This delightfully detailed false color image of Saturn was earmarked to celebrate the 8th anniversary of the orbiting Hubble Space Telescope. The picture is a combination of three images taken in January 1998 and shows the lovely ringed planet in reflected infrared light.

White Rock Fingers on Mars
14.02.2016

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.

The Fornax Cluster of Galaxies
10.06.2016

Named for the southern constellation toward which most of its galaxies can be found, the Fornax Cluster is one of the closest clusters of galaxies. About 62 million light-years away, it is almost...

Lunar Orbiter Earthset
26.08.2016

August 10th was the 50th anniversary of the launch of Lunar Orbiter 1. It was the first of five Lunar Orbiters intended to photograph the Moon's surface to aid in the selection of future landing sites.

Milky Way over Chilean Volcanoes
20.08.2017

Sometimes, the sky mimics the ground. Taken in 2017 May from the Atacama Desert in Chile, the foreground of the featured image encompasses the dipping edge of the caldera of an extinct volcano. Poetically echoing the dip below is the arch of our Milky Way Galaxy above.

Jupiter Engulfed and the Milky Way
6.08.2019

This is a good month to see Jupiter. To find our Solar System's largest planet in your sky, look toward the southeast just after sunset -- Jupiter should be the brightest object in that part of the sky.

The Strange Tailing Side of Saturns Iapetus
10.10.2007

What has happened to Saturn's moon Iapetus? Vast sections of this strange world are dark as coal, while others are as bright as ice. The composition of the dark material is unknown, but infrared spectra indicate that it possibly contains some dark form of carbon.