Millions of Stars in Omega Centauri
3.06.2021

Globular star cluster Omega Centauri, also known as NGC 5139, is some 15,000 light-years away. The cluster is packed with about 10 million stars much older than the Sun within a volume about 150 light-years in diameter.

A Lunar Rille
29.10.2002

What could cause a long indentation on the Moon? First discovered over 200 years ago with a small telescope, rilles (rhymes with pills) appear all over the Moon. Three types of rilles...

Millions of Stars in Omega Centauri
29.05.2014

Globular star cluster Omega Centauri, also known as NGC 5139, is some 15,000 light-years away. The cluster is packed with about 10 million stars much older than the Sun within a volume about...

NGC 6960: The Witch's Broom Nebula
1.01.2003

Ten thousand years ago, before the dawn of recorded human history, a new light must suddenly have appeared in the night sky and faded after a few weeks. Today we know this light was an exploding star and record the colorful expanding cloud as the Veil Nebula.

Millions of Stars in Omega Centauri
28.03.2024

Globular star cluster Omega Centauri, also known as NGC 5139, is 15,000 light-years away. The cluster is packed with about 10 million stars much older than the Sun within a volume about 150 light-years in diameter.

The Doomed Dust Disk of NGC 7052
22.06.1998

What created the dust disk in the center of NGC 7052, and what keeps it spinning? Although the disk might appear as a relatively tame "hubcap in space", the unusual center of elliptical galaxy NGC 7052 is probably the remnant of a titanic collision between galaxies.

M1: The Incredible Expanding Crab
5.09.2013

The Crab Nebula is cataloged as M1, the first on Charles Messier's famous list of things which are not comets. In fact, the Crab is now known to be a supernova remnant, an expanding cloud of debris from the explosion of a massive star.

Millions of Stars in Omega Centauri
16.03.2023

Globular star cluster Omega Centauri, also known as NGC 5139, is 15,000 light-years away. The cluster is packed with about 10 million stars much older than the Sun within a volume about 150 light-years in diameter.

The Radio Sky: Tuned to 408MHz
5.02.2005

Tune your radio telescope to 408MHz (408 million cycles per second) and check out the Radio Sky! In the 1970s large dish antennas at three radio observatories, Jodrell Bank, MPIfR, and Parkes Observatory, were used to do just that - the data were combined to map the entire sky.

APOD: 2025 September 17 Б Nebulas and Clusters in Sagittarius
17.09.2025

Can you spot famous celestial objects in this image? 18th-century astronomer Charles Messier cataloged only two of them: the bright Lagoon Nebula (M8) at the bottom, and the colorful Trifid Nebula (M20) at the upper right.