APOD: 2023 July 30 Б Spiral Aurora over Icelandic Divide
30.07.2023

Admire the beauty but fear the beast. The beauty is the aurora overhead, here taking the form of a great green spiral, seen between picturesque clouds with the bright Moon to the side and stars in the background.

Comet Hyakutake's Past and Future
23.03.1996

The above false-color picture of Comet Hyakutake taken just two days ago shows its rapidly developing tail. The comet now has a substantial coma with a bright center, lending it a dramatic eye-like appearance. This is not Comet Hyakutake's first visit to the inner Solar System.

M27: Not a Comet
26.08.2010

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.

The Rippled Red Ribbons of SNR 0509
25.01.2011

What is causing the picturesque ripples of supernova remnant SNR 0509-67

Wonder and Mystery above the Very Large Telescopes
9.05.2011

What's that bright orange dot above the large telescope on the right? Even seasoned sky enthusiasts might ponder the origin of the orange orb seen by scrolling across this panoramic image, taken last December. Perhaps identifying known objects will help.

APOD: 2023 September 6 Б HESS Telescopes Explore the High Energy Sky
6.09.2023

They may look like modern mechanical dinosaurs, but they are enormous swiveling eyes that watch the sky. The High Energy Stereoscopic System (H.E.S.S.) Observatory is composed of four 12-meter reflecting-mirror telescopes surrounding a larger telescope housing a 28-meter mirror.

APOD: 2026 May 21 Б A Collision of Galaxy Clusters
21.05.2026

This big beautiful spiral shines in X-ray light. It is about 20 times larger than our Galaxy. It belongs to Abell 2029, a galaxy cluster one billion light-years away. (To see only the galaxies...

Supernova Remnant N132D in Optical and X Rays
25.10.2005

Thousands of years after a star exploded, its expanding remnant still glows brightly across the spectrum. Such is the case with N132D, a supernova remnant located in the neighboring Large Magellanic Cloud (LMC) galaxy. The expanding shell from this explosion now spans 80 light-years and has swept up about 600 Suns worth of mass.

Spiral Galaxy NGC 4038 in Collision
12.08.2012

This galaxy is having a bad millennium. In fact, the past 100 million years haven't been so good, and probably the next billion or so will be quite tumultuous. Visible on the upper...

LL Ori and the Orion Nebula
3.02.2013

This esthetic close-up of cosmic clouds and stellar winds features LL Orionis, interacting with the Orion Nebula flow. Adrift in Orion's stellar nursery and still in its formative years, variable star LL Orionis produces a wind more energetic than the wind from our own middle-aged Sun.