Autumn Moon Encore
15.12.2005

Near its northernmost declination, tonight's Full Moon will be a special one, arcing high in northern hemisphere skies. But a Full Moon won't occur on this calendar date for another 19 years, a period known as the lunar Metonic cycle.

Stars and Dust in Corona Australis
18.10.2017

Blue dust clouds and young, energetic stars inhabit this telescopic vista, less than 500 light-years away toward the northern boundary of Corona Australis, the Southern Crown. The dust clouds effectively block light from more distant background stars in the Milky Way.

A Five Quasar Gravitational Lens
24.05.2006

What's happening near the center of this cluster of galaxies? At first glance, it appears that several strangely elongated galaxies and fully five bright quasars exist there. In reality, an entire cluster of galaxies is acting as a gigantic gravitational lens that distorts and multiply-images bright objects that occur far in the distance.

LDN 673: Dark Clouds in Aquila
29.10.2022

Part of a dark expanse that splits the crowded plane of our Milky Way galaxy, the Aquila Rift arcs through planet Earth's skies near bright star Altair. In eerie silhouette against the Milky...

APOD: 2026 May 22 Б The Nebulous Realm of WR 134
22.05.2026

This cosmic snapshot covers a field of view over twice as wide as the full Moon within the boundaries of the high-flying constellation Cygnus. Made using astronomical narrowband filters, the image highlights the bright edge of a ring-like nebula traced by the glow of ionized hydrogen and oxygen gas.

The Colors and Mysteries of Centaurus A
12.08.2002

Why is spiral galaxy Centaurus A in so much turmoil? The above composite image shows different clues to the unusual galaxy's past in different bands of light. In low energy radio waves, shown in red, lobes across the thick swath of dust glow brightly.

Southern Cross Star Colors
8.07.2004

Fix your camera to a tripod, lock the shutter open, and you can easily record an image of star trails, the graceful concentric arcs traced by the stars as planet Earth rotates on its axis.

Solar Shock Wave
30.04.1999

On September 24, 1997 a shock wave blasted across the surface of the sun at speeds of 250 to 600 kilometers per second. On planet Earth, observer Barry Reynolds photographed the expanding shock front (left) in the light emitted by hydrogen atoms at the solar surface.

Stars and Dust Across Corona Australis
3.04.2006

A cosmic dust cloud sprawls across a rich field of stars in this gorgeous wide field telescopic vista looking toward Corona Australis, the Southern Crown. Probably less than 500 light-years away and effectively blocking...

SOHOs Twin Sungrazers
11.06.1998

This four frame animation (courtesy D. Biesecker) shows two comets arcing toward a fatal fiery encounter with the Sun. These discovery images were recorded by the LASCO instrument on board the space-based SOHO solar observatory on June 1-2.