APOD: 2023 July 5 Б A Map of the Observable Universe
5.07.2023

What if you could see out to the edge of the observable universe? You would see galaxies, galaxies, galaxies, and then, well, quasars, which are the bright centers of distant galaxies. To expand understanding...

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.

STARFORGE: A Star Formation Simulation
23.06.2021

How do stars form? Most form in giant molecular clouds located in the central disk of a galaxy. The process is started, influenced, and limited by the stellar winds, jets, high energy starlight, and supernova explosions of previously existing stars.

Two Black Holes Dancing in 3C 75
5.06.2022

What's happening at the center of active galaxy 3C 75? The two bright sources at the center of this composite x-ray (blue)/ radio (pink) image are co-orbiting supermassive black holes powering the giant radio source 3C 75.

Hubble s Messier 5
25.04.2014

"Beautiful Nebula discovered between the Balance [Libra] & the Serpent [Serpens] ..." begins the description of the 5th entry in 18th century astronomer Charles Messier's famous catalog of nebulae and star clusters. Though it appeared...

Hubble s Messier 5
20.06.2015

"Beautiful Nebula discovered between the Balance [Libra] & the Serpent [Serpens] ..." begins the description of the 5th entry in 18th century astronomer Charles Messier's famous catalog of nebulae and star clusters. Though it appeared...

The Supermassive Black Holes of NGC 6240
28.11.2002

The Hubble optical image on the left shows NGC 6240 in the throes of a titanic galaxy - galaxy collision 400 million light-years away. As the cosmic catastrophe plays out, the merging galaxies spew forth distorted tidal tails of stars, gas, and dust and undergo frantic bursts of star formation.

The Holographic Principle
16.12.2007

Is this picture worth a thousand words? According to the Holographic Principle, the most information you can get from this image is about 3 x 10 65 bits for a normal sized computer monitor.

The Holographic Principle
18.05.2003

Is this image worth a thousand words? According to the Holographic Principle, the most information you can get from this image is about 3 x 10⁶⁵ bits for a normal sized computer monitor.

Lunar Prospects
18.09.1998

Launched on January 6th, NASA's Lunar Prospector spacecraft has been exploring the Moon with instruments designed to sense global properties while orbiting pole-to-pole, 63 miles above the lunar surface. Now over half...