M27: Not a Comet
1.09.2011

While hunting for comets in the skies above 18th century France, astronomer Charles Messier diligently kept a list of the things he encountered that were definitely not comets. This is number 27 on his now famous not-a-comet list.

M46 and M47: Star Clusters Young and Old
3.04.2012

Many stars form in clusters. Galactic or open star clusters are relatively young swarms of bright stars born together near the plane of our Milky Way Galaxy. Separated by about a degree...

Comet Lemmon near the South Celestial Pole
7.02.2013

Currently sweeping through southern skies, Comet Lemmon (C/2012 F6) was named for its discovery last year as part of the Mount Lemmon (Arizona) Survey. Brighter than expected but still just below naked-eye visibility, Comet Lemmon sports a stunning lime green coma and faint divided tail in this telescopic image from February 4.

MAVEN at Mars
26.09.2014

Launched on November 18, 2013, the MAVEN (Mars Atmosphere and Volatile EvolutioN) spacecraft completed its interplanetary voyage September 21, captured into a wide, elliptical orbit around Mars. MAVEN's imaging ultraviolet spectrograph has already...

A Total Solar Eclipse Reflected
4.08.2019

If you saw a total solar eclipse, would you do a double-take? One astrophotographer did just that -- but it took a lake and a bit of planning. Realizing that the eclipse would...

HD 163296: Jet from a Star in Formation
21.06.2021

How are jets created during star formation? No one is sure, although recent images of the young star system HD 163296 are quite illuminating. The central star in the featured image is still forming but seen already surrounded by a rotating disk and an outward moving jet.

Centaurus A: X-Rays from an Active Galaxy
5.07.2003

Its core hidden from optical view by a thick lane of dust, the giant elliptical galaxy Centaurus A was among the first objects observed by the orbiting Chandra X-ray Observatory. Astronomers were not disappointed, as Centaurus A's appearance in x-rays makes its classification as an active galaxy easy to appreciate.

APOD: 2008 June 17- Eta Carinae and the Homunculus Nebula
17.06.2008

How did the star Eta Carinae create this unusual nebula? No one knows for sure. About 165 years ago, the southern star Eta Carinae mysteriously became the second brightest star in the night sky. In 20 years, after ejecting more mass than our Sun, Eta Car unexpected faded.

International Space Station: Find the Astronaut
1.12.2008

Where's the astronaut? Somewhere in this impressive array of International Space Station (ISS) hardware, astronaut Steve Bowen can be found upgrading and cleaning key parts of Earth's most prominent orbital outpost. Astronaut...

Comet Lovejoy and the ISS
31.12.2011

On December 24, Comet Lovejoy rose in dawn's twilight, arcing above the eastern horizon, its tails swept back by the solar wind and sunlight. Seen on the left is the comet's early morning appearance alongside the southern Milky Way from the town of Intendente Alvear, La Pampa province, Argentina.