APOD: 2023 May 28 Б Ida and Dactyl: Asteroid and Moon
28.05.2023

This asteroid has a moon. The robot spacecraft Galileo on route to Jupiter in 1993 encountered and photographed two asteroids during its long interplanetary voyage. The second minor planet it photographed, 243 Ida, was unexpectedly discovered to have a moon.

APOD: 2025 July 23 Б Fireball over Cape San Blas
23.07.2025

Have you ever seen a fireball? In astronomy, a fireball is a very bright meteor -- one at least as bright as Venus and possibly brighter than even a full Moon. Fireballs are rare -- if you see one you are likely to remember it for your whole life.

APOD: 2024 March 27 Б The Coma Cluster of Galaxies
27.03.2024

Almost every object in the featured photograph is a galaxy. The Coma Cluster of Galaxies pictured here is one of the densest clusters known - it contains thousands of galaxies. Each of these galaxies houses billions of stars - just as our own Milky Way Galaxy does.

APOD: 2024 September 11 Б A Night Sky over the Tatra Mountains
11.09.2024

A natural border between Slovakia and Poland is the Tatra Mountains. A prominent destination for astrophotographers, the Tatras are the highest mountain range in the Carpathians. In the featured image taken...

APOD: 2026 January 14 Б M51: The Whirlpool Galaxy
14.01.2026

The Whirlpool Galaxy is a classic spiral galaxy. At only 30 million light years distant and fully 60 thousand light years across, M51, also known as NGC 5194, is one of the brightest and most picturesque galaxies on the sky.

APOD: 2025 September 23 Б NGC 6357: Cathedral to Massive Stars
23.09.2025

How massive can a normal star be? Estimates made from distance, brightness and standard solar models had given one star in the open cluster Pismis 24 over 200 times the mass of our Sun, making it one of the most massive stars known.

APOD: 2023 April 10 Б IC 2944: The Running Chicken Nebula
10.04.2023

To some, it looks like a giant chicken running across the sky. To others, it looks like a gaseous nebula where star formation takes place. Cataloged as IC 2944, the Running Chicken Nebula spans about 100 light years and lies about 6,000 light years away toward the constellation of the Centaur (Centaurus).

APOD: 2025 November 17 Б Comet Lemmons Wandering Tail
17.11.2025

What has happened to Comet Lemmon's tail? The answer is blowing in the wind Б the wind from the Sun in this case. This continuous outflow of charged particles from...

APOD: 2009 April 6 The International Space Station Expands Again
6.04.2009

The developing International Space Station (ISS) has changed its appearance again. In a recently completed mission, the Space Shuttle orbiter Discovery visited the ISS and added components that included a new truss and new solar panels.

APOD: 2025 June 14 Б Meteors and Satellite Trails over the Limay River
14.06.2025

What are all those streaks in the sky? A galaxy, many satellite trails, and a few meteors. First, far in the distance, the majestic band of our Milky Way Galaxy runs down the left. Mirroring it on the right are several parallel trails of Earth-orbiting Starlink satellites. Many fainter satellite trails also crisscross the image.