A Martian Metamorphosis
4.06.2002

Is it an Escher, or Mars? Three different types of surfaces visible in the North Polar Cap of Mars morph into each other in a way perhaps reminiscent of the works of M. C. Escher. On the far left dark sand covers the ground, while the center shows a transition to a dune field.

Water Found in Space Rock
7.09.1999

What would you do if it rained blue water from space? On 1998 March 22, no umbrella was needed, as the blue water came attached to a stony meteorite that landed in Monahans, Texas. The meteorite fall was seen by several boys, and was being carefully scrutinized by NASA scientists within 72 hours.

The Pipe Nebula
23.11.2012

East of Antares, dark markings sprawl through crowded star fields toward the center of our Milky Way Galaxy. Cataloged in the early 20th century by astronomer E. E. Barnard, the obscuring interstellar dust clouds include B59, B72, B77 and B78, seen in silhouette against the starry background.

Light Echoes from V838 Mon
26.06.2022

What caused this outburst of V838 Mon? For reasons unknown, star V838 Mon's outer surface suddenly greatly expanded with the result that it became one of the brighter stars in the Milky Way Galaxy in early 2002. Then, just as suddenly, it shrunk and faded.

Water Ice in a Maritan Crater
20.07.2005

What lies on the floor of this Martian crater? A frozen patch of water ice. The robotic Mars Express spacecraft took the above image in early February. The ice pocket was found in a 35-kilometer wide crater that resides 70 degrees north of the Martian equator.

Comet McNaught Heads for the Sun
5.01.2007

Early morning risers with a clear and unobstructed eastern horizon can enjoy the sight of Comet McNaught (C/2006 P1) in dawn skies over the next few days. Discovered in August by R. H. McNaught...

APOD: 2025 February 24 Б Light Pillar over Erupting Etna
24.02.2025

Can a lava flow extend into the sky? No, but light from the lava flow can. One effect is something quite unusual -- a volcanic light pillar. More typically, light pillars are caused by sunlight and so appear as a bright column that extends upward above a rising or setting Sun.

Snake in the Dark
20.06.2003

Dark nebulae snake across a gorgeous expanse of stars in this wide-field view toward the pronounceable constellation Ophiucus and the center of our Milky Way Galaxy. In fact, the central S-shape seen here is well known as the Snake Nebula.

Jupiter and the Moon s Shadowed Horizon
9.12.2004

Early Tuesday morning, December 7th, June Croft thought the southeastern sky above Atmore, Alabama, USA was beautiful. Watching the Moon rise through gossamer clouds, she noted, " ... the crescent Moon looked like it was held in the sky by a star just off its shadowed horizon." What was that star?

Titan Surmised
20.12.2004

What does the surface of Titan look like? Thick clouds have always made Saturn's largest moon so mysterious that seemingly farfetched hypotheses like methane rain and lakes have been seriously considered. Later this...