The Necklace Nebula
3.11.2010

The small constellation Sagitta sports this large piece of cosmic jewelry, dubbed the Necklace Nebula. The newly discovered example of a ring-shaped planetary nebula is about 15,000 light-years distant. Its bright ring with pearls of glowing gas is half a light-year across.

The Light of Stars
8.05.2012

What's moving? Time lapse videos of the sky can be quite spectacular when they last long enough for stars, planets, aurora, and clouds to appear to move in just a few seconds. Pictured...

Journey to the Center of the Galaxy
2.07.2012

What wonders lie at the center of our Galaxy? In Jules Verne's science fiction classic A Journey to the Center of the Earth, Professor Liedenbrock and his fellow explorers encounter many strange and exciting wonders.

Southern Annular Eclipse
26.04.2014

It's eclipse season, and on April 29 around 06:00 UT the shadow of the new Moon will reach out and touch planet Earth, though only just. Still, if you're standing...

NGC 253: Dusty Island Universe
22.03.2018

Shiny NGC 253 is one of the brightest spiral galaxies visible, and also one of the dustiest. Some call it the Silver Dollar Galaxy for its appearance in small telescopes, or just the Sculptor Galaxy for its location within the boundaries of the southern constellation Sculptor.

A Plurality of Singularities at the Galactic Center
12.05.2018

A recent informal poll found that astronomers don't yet have a good collective noun for a group of black holes, but they need one. The red circles in this Chandra Observatory X-ray image identify a group of a dozen black holes that are members of binary star systems.

The Orion You Can Almost See
21.08.2019

Do you recognize this constellation? Although it is one of the most recognizable star groupings on the sky, this is a more full Orion than you can see -- an Orion only revealed with long exposure digital camera imaging and post-processing.

NGC 6164: Dragons Egg Nebula and Halo
26.12.2022

The star at the center created everything. Known as the Dragon's Egg, this star -- a rare, hot, luminous O-type star some 40 times as massive as the Sun -- created not only the complex nebula (NGC 6164) that immediately surrounds it, but also the encompassing blue halo.

APOD: 2023 May 21 Б Tardigrade in Moss
21.05.2023

Is this an alien? Probably not, but of all the animals on Earth, the tardigrade might be the best candidate. That's because tardigrades are known to be able to go for decades without...

Stickney Crater
8.07.2023

Stickney Crater, the largest crater on the martian moon Phobos, is named for Chloe Angeline Stickney Hall, mathematician and wife of astronomer Asaph Hall. Asaph Hall discovered both the Red Planet's moons in 1877.