IC 418: The Spirograph Nebula
7.09.2000

What is creating the strange texture of IC 418? Dubbed the Spirograph Nebula for its resemblance to drawings from a cyclical drawing tool, planetary nebula IC 418 shows patterns that are not well understood. Perhaps they are related to chaotic winds from the variable central star, which changes brightness unpredictably in just a few hours.

Fireball, Smoke Trail, Meteor Storm
22.11.2001

Returning from orbit, space shuttles enter the atmosphere at about 8 kilometers per second as friction heats their protective ceramic tiles to over 1,400 degrees Celsius. By contrast, the bits of comet dust...

Gamma Ray Bursts from the Unknown
27.08.1995

Gamma Ray Bursts (GRBs) pose one of the greatest mysteries of modern astronomy. About once a day, the gamma-ray sky lights up with a spectacular explosion. No one knows what causes these explosions or even how far away they are.

Young Star Cluster Westerlund 2
26.06.2010

Dusty stellar nursery RCW 49 surrounds young star cluster Westerlund 2 in this remarkable composite skyscape from beyond the visible spectrum of light. Infrared data from the Spitzer Space Telescope is shown in black...

The North America Nebula in Infrared
15.02.2011

The North America Nebula can do what most North Americans cannot -- form stars. Precisely where in the nebula these stars are forming has been mostly obscured by some of the nebula's thick dust that is opaque to visible light.

M27: Not a Comet
20.08.2015

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.

M82: Galaxy with a Supergalactic Wind
23.07.2019

Why is the Cigar Galaxy billowing red smoke? M82, as this starburst galaxy is also known, was stirred up by a recent pass near large spiral galaxy M81. This doesn't fully explain the source of the red-glowing outwardly expanding gas and dust, however.

APOD: 2024 October 20 Б Dark Matter in a Simulated Universe
20.10.2024

Is our universe haunted? It might look that way on this dark matter map. The gravity of unseen dark matter is the leading explanation for why galaxies rotate so fast, why galaxies orbit clusters...

Apollo Surveyor Stereo View
10.03.2001

Put on your red/blue glasses and gaze into this dramatic stereo view from the surface of the Moon! Inspired by last Saturday's APOD, Patrick Vantuyne offers this stereo rendering of the captivating picture of Apollo 12 astronaut Pete Conrad visiting the Surveyor

Visitors Galaxy Gallery
18.06.2005

A tantalizing assortment of island universes is assembled here. From top left to bottom right are the lovely but distant galaxies M61, NGC 4449, NGC 4725, NGC 5068, NGC 5247, and NGC 5775/5774. Most are spiral galaxies more or less like our own Milky Way.