Distant Open Cluster M103
7.02.2001

Bright blue stars highlight the open cluster known as M103. The gas clouds from which these stars condensed has long dispersed. Of the stars that were formed, the brightest, bluest, and most massive have already used up their nuclear fuel and self-destructed in supernova explosions.

Comet 57P Falls to Pieces
2.08.2002

Comet 57P has fallen to pieces, at least 19 of them. Orbiting the Sun every 5.9 years or so this faint comet - also christened Comet 57P/du Toit-Neujmin-Delporte for its three 1941 co-discoverers - is simply...

Vesta Near Opposition
18.02.2010

Main belt asteroid 4 Vesta is at its brightest now. The small world is near opposition (opposite the Sun in the sky) and closest to Earth. But even at its brightest, Vesta is just too faint to spot with the naked-eye.

Opportunity at Santa Maria Crater
29.01.2011

Celebrating 7 years on the surface of the Red Planet, Mars exploration rover Opportunity now stands near the rim of 90 meter wide Santa Maria crater. Remarkably, Opportunity and its fellow rover Spirit were initially intended for a 3 month long primary mission.

Airglow, Gegenschein, and Milky Way
20.04.2013

As far as the eye could see, it was a dark night at Las Campanas Observatory in the southern Atacama desert of Chile. But near local midnight on April 11, this mosaic of 3 minute long exposures revealed a green, unusually intense, atmospheric airglow stretching over thin clouds.

Retrograde Mars and Saturn
15.09.2016

Wandering Mars and Saturn have spent much of this year remarkably close in planet Earth's night sky. In a sequence of exposures spanning mid-December 2015 through the beginning of this week, this composited...

Sharpless 308: The Dolphin Nebula
2.03.2020

Blown by fast winds from a hot, massive star, this cosmic bubble is much larger than the dolphin it appears to be. Cataloged as Sharpless 2-308 it lies some 5,200 light-years away toward the constellation of the Big Dog (Canis Major) and covers slightly more of the sky than a Full Moon.

NGC 6357: Cathedral to Massive Stars
30.08.2020

How massive can a normal star be? Estimates made from distance, brightness and standard solar models had given one star in the open cluster Pismis 24 over 200 times the mass of our Sun, making it one of the most massive stars known.

M27: Not a Comet
5.10.2024

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

Tempel Tuttle: The Leonid Comet
16.11.2002

Star trails streak this composite time exposure of comet Tempel-Tuttle recorded by Tim Puckett on January 26, 1998. Then passing through the inner solar system on its 33 year orbit around the Sun, Tempel-Tuttle brightened unexpectedly, but binoculars or small telescopes were still required to visually observe it.