Gamma Ray Bursting
4.11.1999

Using graphics and data from NASA's Compton Gamma Ray Observatory, this animation illustrates one of the most exciting mysteries of modern astrophysics, gamma-ray bursts. Incredibly gamma-ray bursts, sudden flashes of radiation with over 100,000 times the energy of visible light photons, occur several times a day.

Gamma Ray Moon
17.04.1999

What if you could see gamma rays (photons with more than 40 million times the energy of visible light)? If you could, the Moon would appear brighter than the Sun! This startling notion...

A Happy Sky Over Los Angeles
3.12.2008

Sunday, the sky seemed to smile over much of planet Earth. Visible the world over was an unusual superposition of our Moon and the planets Venus and Jupiter. Pictures taken at the right time...

A Galactic Cloud of Antimatter
1.05.1997

The center of our Milky Way Galaxy is full of surprises. Its latest spectacular is a mysterious cloud glowing in gamma rays produced by annihilating antimatter particles! Star Trek fans are all too familiar...

Elements in the Aftermath
1.08.2019

Massive stars spend their brief lives furiously burning nuclear fuel. Through fusion at extreme temperatures and densities surrounding the stellar core, nuclei of light elements ike Hydrogen and Helium are combined to heavier elements like Carbon, Oxygen, etc. in a progression which ends with Iron.

GRB 090423: The Farthest Explosion Yet Measured
29.04.2009

An explosion so powerful it was seen clear across the visible universe was recorded in gamma-radiation last week by NASA's orbiting Swift Observatory. Farther than any known galaxy, quasar, or optical supernova, the gamma-ray burst recorded last week was clocked at redshift 8.2, making it the farthest explosion of any type yet detected.

A Happy Sky over Los Angeles
12.11.2017

Sometimes, the sky may seem to smile over much of planet Earth. On this day in 2008, visible the world over, was an unusual superposition of our Moon and the planets Venus and Jupiter.

Two Hemisphere Night Sky
27.02.2020

The Sun is hidden by a horizon that runs across the middle in this two hemisphere view of Earth's night sky. The digitally stitched mosaics were recorded from corresponding latitudes, one 29 degrees north and one 29 degrees south of the planet's equator.

APOD: 2024 July 23 Б The Crab Nebula from Visible to X Ray
23.07.2024

What powers the Crab Nebula? A city-sized magnetized neutron star spinning around 30 times a second. Known as the Crab Pulsar, it is the bright spot in the center of the gaseous swirl at the nebula's core.

APOD: 2025 October 10 Б 50 Light-years to 51 Pegasi
10.10.2025

It's only 50 light-years to 51 Pegasi. That star's position is indicated in this snapshot from August 2025, taken on a night with mostly brighter stars visible above the dome at Observatoire de Haute-Provence in France.