APOD: 2026 February 23 Б Pleiades: The Seven Sisters Star Cluster
23.02.2026

Have you ever seen the Pleiades star cluster? Even if you have, you probably have never seen it as large and clear as this. Perhaps the most famous star cluster on the sky, the bright stars of the Pleiades can be seen with the unaided eye even from the depths of a light-polluted city.

The Hydra Cluster of Galaxies
16.02.2023

Once upon a midnight dreary, while I pondered weak and weary, O'er volumes of astronomy and forgotten lore, I stumbled upon this snapshot, cosmic and eerie, A sight that filled my heart with awe and more.

Star Clusters Young and Old
10.09.2006

Many stars form in clusters. Galactic or open star clusters are relatively young swarms of bright stars born together near the plane of our Milky Way Galaxy. Separated by about a degree...

The Center of Globular Cluster Omega Centauri
10.10.2001

What is left over after stars collide? To help answer this question, astronomers have been studying the center of the most massive ball of stars in our Milky Way Galaxy. In the center of globular cluster Omega Centauri, stars are packed in 10,000 times more densely than near our Sun.

Young Star Cluster Westerlund 2
31.01.2008

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...

Abell 370: Galaxy Cluster Gravitational Lens
19.03.2019

What are those strange arcs? While imaging the cluster of galaxies Abell 370, astronomers noticed an unusual arc. The arc wasn't understood right away -- not until better images showed that...

NGC 1898: Globular Cluster in the LMC
3.10.2018

Jewels don't shine this bright -- only stars do. And almost every spot in this glittering jewel-box of an image from the Hubble Space Telescope is a star. Now some stars are more red than our Sun, and some more blue -- but all of them are much farther away.

A Blue Bridge of Stars between Cluster Galaxies
15.07.2014

Why is there a blue bridge of stars across the center of this galaxy cluster? First and foremost the cluster, designated SDSS J1531+3414, contains many large yellow elliptical galaxies. The cluster's center...

The Center of Globular Cluster Omega Centauri
14.09.2009

What is left over after stars collide? To help answer this question, astronomers have been studying the center of the most massive ball of stars in our Milky Way Galaxy. In the center of globular cluster Omega Centauri, stars are packed in 10,000 times more densely than near our Sun.

NGC 346: Star Forming Cluster in the SMC
1.12.2020

Are stars still forming in the Milky Way's satellite galaxies? Found among the Small Magellanic Cloud's (SMC's) clusters and nebulas, NGC 346 is a star forming region about 200 light-years across, pictured here in the center of a Hubble Space Telescope image.