Rainbow Airglow over the Azores
18.04.2021

Why would the sky glow like a giant repeating rainbow? Airglow. Now air glows all of the time, but it is usually hard to see. A disturbance however -- like an approaching storm -- may cause noticeable rippling in the Earth's atmosphere.

Messier 76
23.07.2010

"Nebula at the right foot of Andromeda ... " begins the description for the 76th object in Charles Messier's 18th century Catalog of Nebulae and Star Clusters. In fact, M76 is one of the fainter objects on the Messier list and is also known by the popular name of the "Little Dumbbell Nebula".

Rainbow Airglow over the Azores
22.03.2016

Why would the sky glow like a giant repeating rainbow? Airglow. Now air glows all of the time, but it is usually hard to see. A disturbance however -- like an approaching storm -- may cause noticeable rippling in the Earth's atmosphere.

UGC 1810: Wildly Interacting Galaxy from Hubble
18.10.2020

What's happening to this spiral galaxy? Although details remain uncertain, it surely has to do with an ongoing battle with its smaller galactic neighbor. The featured galaxy is labelled UGC 1810 by itself, but together with its collisional partner is known as Arp 273.

APOD: 2023 May 31 Б Simulation: A Disk Galaxy Forms
31.05.2023

How did we get here? We know that we live on a planet orbiting a star orbiting a galaxy, but how did all of this form? Since our universe moves too slowly to watch, faster-moving computer simulations are created to help find out.

APOD: 2025 June 3 Б Rainbow Airglow over the Azores
3.06.2025

Why would the sky glow like a giant repeating rainbow? Airglow. Now, air glows all of the time, but it is usually hard to see. A disturbance however -- like an approaching storm -- may cause noticeable rippling in the Earth's atmosphere.

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...

The Colliding Galaxies of NGC 520
12.09.2005

Is this one galaxy or two? The jumble of stars, gas, and dust that is NGC 520 is now thought to incorporate the remains of two separate galaxies. A combination of observations and simulations indicate the NGC 520 is actually the collision of two disk galaxies.

Across the Universe
28.03.2008

How far can you see? Even the faintest stars visible to the eye are merely hundreds or thousands of light-years distant, all well within our own Milky Way Galaxy. Of course, if you know where to look you can also spot the Andromeda Galaxy as a pale, fuzzy cloud, around 2.5 million light-years away.

Voorwerpjes in Space
4.04.2015

Mysterious Hanny's Voorwerp, Dutch for "Hanny's Object", is really enormous, about the size of the Milky Way Galaxy and glowing strongly in the greenish light produced by ionized oxygen atoms.