Geostationary Satellites Beyond the Alps
11.04.2012

Why don't those stars move? Stars in the sky will typically appear to rise and set as the Earth turns. Those far to the north or south will appear to circle the pole. If you look closely at the above time-lapse movie, however, there are points of light that appear stationary.

Saturns Moon Dione in Slight Color
5.11.2012

Why does one half of Dione have more craters than the other? Start with the fact that Saturn's moon Dione has one side that always faces Saturn, and one side that always faces away. This is similar to Earth's Moon.

PanSTARRS over Parkes
9.03.2013

Sweeping quickly through southern skies on March 5, Comet PanSTARRS (C/2011 L4) follows the Sun toward the western horizon in this twilight scene. In the foreground is Australia's CSIRO Parkes Radio Telescope, a 64 meter wide steerable dish that is no stranger to the space age exploration of comets.

Fresh Tiger Stripes on Saturns Enceladus
6.04.2014

Do underground oceans vent through the tiger stripes on Saturn's moon Enceladus? Long features dubbed tiger stripes are known to be spewing ice from the moon's icy interior into space, creating a cloud of fine ice particles over the moon's South Pole and creating Saturn's mysterious E-ring.

Fly Over Dwarf Planet Ceres
9.06.2015

What would it look like to fly over dwarf planet Ceres? Animators from the German Aerospace Center recently took actual images and height data from NASA's robotic Dawn mission -- currently visiting Ceres -- to generate several fascinating virtual sequences.

APOD: 2025 July 15 Б Collapse in Hebes Chasma on Mars
14.07.2025

What's happened in Hebes Chasma on Mars? Hebes Chasma is a depression just north of the enormous Valles Marineris canyon. Since the depression is unconnected to other surface features, it is unclear where the internal material went.

Sunbather
10.01.2002

Intense and overwhelming, the direct glare of the Sun is blocked by the smooth disk centered in this image from the sun-staring SOHO spacecraft. Taken on January 8, the picture shows streamers of solar wind billowing radially outward for millions of kilometers above the Sun's surface indicated by the white circle.

Explosions Discovered Near Galactic Center
27.02.1996

Tremendous explosions near the center of our Galaxy were discovered just this past December and are being announced today by a paper in Nature and a press conference at NASA. Bursts like these have...

Solar Moss
26.12.1999

Discovered in recent close-up pictures of the Sun from NASA's Transition Region And Coronal Explorer (TRACE) spacecraft, this spongy-looking stuff has a temperature of 2 million degrees Fahrenheit ... and has been dubbed "Solar Moss". The false-color TRACE image above was recorded in extreme ultraviolet light on October 18.

Mysterious Acid Haze on Venus
25.02.2008

Why did an acidic haze spread across Venus? The unusual clouds were discovered last July by ESA's robotic Venus Express spacecraft currently orbiting Venus. The bright and smooth haze was found by Venus...