APOD: 2026 June 3 Б Andromeda Through Gas and Dust
3.06.2026

Over 1000 years ago, Persian astronomer Abd al-Rahman al-Sufi published humanityБs oldest known record of the Andromeda Galaxy in "The Book of Fixed Stars" (Bodleian Library MS. Marsh 144 p. 167). 800 years later, Andromeda became the 31st entry in Charles MessierБs "Catalogue of Nebulae and Star Clusters".

Counting Stars in the Infrared Sky
19.07.2002

The bulging center of our Milky Way Galaxy, dark cosmic clouds, the thin galactic plane, and even nearby galaxies are easy to spot in this sky view. But each pixel in the digital image is actually based on star counts alone -- as derived from the Two Micron All Sky Survey (2MASS) database.

Gamma-Ray Burster
19.03.1997

What and where are the Gamma-Ray Bursters? Since their discovery in the early 1970s, nobody has been able to explain the cause of mysterious flashes of gamma rays that come from seemingly random directions on the sky.

M51: Cosmic Whirlpool
28.04.2005

Follow the handle of the Big Dipper away from the dipper's bowl, until you get to the handle's last bright star. Then, just slide your telescope a little south and west and you might find this stunning pair of interacting galaxies, the 51st entry in Charles Messier's famous catalog.

NGC 6712: Galactic Globular Cluster
25.02.1999

Following orbits which loop high above the galactic plane, globular star clusters are probably 12 to 14 billion years old - truly ancient denizens of our Milky Way Galaxy. After analyzing these new ESO/VLT images...

Weak Lensing Distorts the Universe
30.03.2008

Is the distant universe really what it appears to be? Astronomers hope not. Intervening dark matter, which is normally invisible, might show its presence by distorting images originating in the distant universe, much the way an old window distorts images originating on the other side.

Herschel s Andromeda
2.02.2013

This infrared view from the Herschel Space Observatory explores the Andromeda Galaxy, the closest large spiral galaxy to our own Milky Way. Only 2.5 million light-years distant, the famous island universe is also known to astronomers as M31. Andromeda spans over 200,000 light-years making it more the twice the size of the Milky Way.

APOD: 2025 August 4 Б Blue Arcs Toward Andromeda
4.08.2025

What are these gigantic blue arcs near the Andromeda Galaxy (M31)? Discovered in 2022 by amateur astronomers, the faint arcs -- dubbed SDSO 1 -- span nearly the same angular size as M31 itself. At first, their origin was a mystery: are they actually near the Andromeda Galaxy, or alternatively near to our Sun?

The Once and Future Stars of Andromeda
23.05.2022

This picture of Andromeda shows not only where stars are now, but where stars will soon be. Of course, the big, beautiful Andromeda Galaxy, M31, is a spiral galaxy -- and a mere 2.5 million light-years away.

The Once and Future Stars of Andromeda
7.10.2023

This picture of Andromeda shows not only where stars are now, but where stars will be. The big, beautiful Andromeda Galaxy, M31, is a spiral galaxy a mere 2.5 million light-years away. Image data...