Moon Rays over Byurakan Observatory
26.09.2008

On September 7th, the first quarter Moon and passing clouds contributed to a dramatic night sky over the Byurakan Astrophysical Observatory. This panoramic view begins at the left looking toward the eastern horizon and the rising stars of the constellation Perseus.

Ganymede: A Really Groovy Moon
11.07.1996

Ganymede's surface is a wrinkled mess. As large ice-sheets shift on the moon's surface, parts of the surface buckle causing high ridges, deep furrows, and parallel grooves. This photo, taken by the Galileo spacecraft currently orbiting Jupiter, was released yesterday. The large circular feature near the picture bottom is a large impact crater.

The Milky Ring
22.01.2021

An expanse of cosmic dust, stars and nebulae along the plane of our Milky Way galaxy form a beautiful ring in this projected all-sky view. The creative panorama covers the entire galaxy visible from planet Earth, an ambitious 360 degree mosaic that took two years to complete.

TrES 2b: Dark Planet
22.08.2011

Why is this planet so dark? Planet TrES-2b reflects back less than one percent of the light it receives, making it darker than any known planet or moon, darker even than coal. Jupiter-sized TrES-2b...

Persistent Saturnian Auroras
22.06.2014

Are Saturn's auroras like Earth's? To help answer this question, the Hubble Space Telescope and the Cassini spacecraft monitored Saturn's South Pole simultaneously as Cassini closed in on the gas giant in January 2004. Hubble snapped images in ultraviolet light, while Cassini recorded radio emissions and monitored the solar wind.

APOD: 2026 January 25 Б Phobos: Doomed Moon of Mars
25.01.2026

This moon is doomed. Mars, the red planet named for the Roman god of war, has two tiny moons, Phobos and Deimos, whose names are derived from the Greek for Fear and Panic. These...

APOD: 2026 April 19 Б Eye on the Milky Way
19.04.2026

Have you ever had stars in your eyes? It appears that the eye on the left does, and moreover, it appears to be gazing at even more stars. The featured 27-frame mosaic was taken in 2019 from Ojas de Salar in the Atacama Desert of Chile.

X Ray Saturn
12.03.2004

Above, the ringed planet Saturn shines in x-rays. Otherwise beyond the range of human vision, the eerie x-ray view was created by overlaying a computer generated outline of the gas giant's disk and ring system on a false-color picture of smoothed, reconstructed x-ray data from the orbiting Chandra Observatory.

Halley Dust and Milky Way
10.05.2019

Grains of cosmic dust streaked through the mostly moonless night skies of May 7. Swept up as planet Earth plowed through the debris streams left behind by periodic Comet Halley, the annual meteor shower is known as the Eta Aquarids.

APOD: 2023 January 2 Б After Sunset Planet Parade
2.01.2023

Look up tonight and see a whole bunch of planets. Just after sunset, looking west, planets Venus, Saturn, Jupiter and Mars will all be simultaneously visible. Listed west to east, this planetary lineup will have Venus nearest the horizon, but setting shortly after the Sun.