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...

I Zwicky 18: The Case of the Aging Galaxy
17.10.2007

How old is this galaxy? The galaxy on the left, I Zwicky 18, was once thought to be one of the youngest galaxies on record since its bright stars indicated an age of only 500 million years.

Cometary Globules
12.10.2013

Bright-rimmed, flowing shapes gather near the center of this rich starfield toward the boarders of the nautical southern constellations Pupis and Vela. Composed of interstellar gas and dust, the grouping of light-year sized cometary globules is about 1300 light-years distant.

Lucy Launches to Eight Asteroids
20.10.2021

Why would this mission go out as far as Jupiter -- but then not visit Jupiter? Lucy's plan is to follow different leads about the origin of our Solar System than can be found at Jupiter -- where Juno now orbits.

APOD: 2023 August 22 Б The Pistachio Nebula
22.08.2023

This nebula had never been noted before. Newly discovered nebulas are usually angularly small and found by professionals using large telescopes. In contrast, the Pistachio Nebula was discovered by dedicated amateurs and, although faint, is nearly the size of the full Moon.