Simulation: A Disk Galaxy Forms
17.07.2012

How do galaxies like our Milky Way form? Since our universe moves too slowly to watch, faster-moving computer simulations are created to help find out. Green depicts (mostly) hydrogen gas in the above movie, while time is shown in billions of years since the Big Bang on the lower right.

Optical Transient Near GRB970508 Shows Distant Redshift
13.05.1997

The GRB distance scale controversy may have just ended with a flash. Gamma Ray Bursts (GRBs) are powerful explosions occurring in seemingly random positions on the sky. They are so featureless and so poorly resolved, however, that their distances could not be determined.

Tycho and Clavius at Dawn
16.07.2022

South is up in this dramatic telescopic view of the lunar terminator and the Moon's rugged southern highlands. The lunar landscape was captured on July 7 with the moon at its first quarter phase.

25 Years Ago: Vikings on Mars
21.07.2001

On July 20, 1976, NASA's Viking 1 lander become the first spacecraft to land on Mars, followed weeks later by its twin robot explorer, the Viking 2 lander. Operating on the Martian surface...