Night in the Andes Ice Forest
7.09.2013

This forest of snow and ice penitentes reflects moonlight shinning across the Chajnantor plateau. The region lies in the Chilean Andes at an altitude of 5,000 meters, not far from one of planet Earth's major astronomical observatories, the Atacama Large Millimeter/submillimeter Array.

Geostationary Highway through Orion
15.01.2017

Put a satellite in a circular orbit about 42,000 kilometers from the center of the Earth and it will orbit once in 24 hours. Because that matches Earth's rotation period, it is known as a geosynchronous orbit.

APOD: 2025 March 3 Б Blue Ghost on the Moon
2.03.2025

There's a new lander on the Moon. Yesterday Firefly Aerospace's Blue Ghost executed the first-ever successful commercial lunar landing. During its planned 60-day mission, Blue Ghost will deploy several NASA-commissioned scientific instruments, including PlanetVac which captures lunar dust after creating a small whirlwind of gas.

THEMIS of Mars
1.11.2001

Not an ancient Greek goddess, THEMIS is modern acronese for THermal EMission Imaging System. Above is this remarkable instrument's premier infrared image of Mars, from the newly orbiting Mars Odyssey spacecraft. Taken...

Solar Wind And Milky Way
3.03.1997

The Sun is bright, so bright that it overwhelms the light from other stars even for most satellite-borne telescopes. But LASCO, a coronograph onboard the space-based SOHO Observatory, uses occulting disks to block the intense solar light and examine the tenuous, hot gases millions of miles above the Sun's surface.

Boosting Compton
6.06.1997

Even great observatories need a boost from time to time -- including the orbiting Compton Gamma-Ray Observatory. Sparkling reflections and the bright limb of the Earth are visible in this 1991 window view of Compton's release into orbit by the crew of the Space Shuttle Atlantis.

Mars Moons
24.10.2003

This year's record close approach of Mars inspired many to enjoy telescopic views of the red planet. But while Mars was so bright it was hard to miss, spotting Mars' two diminutive moons was still a good test for observers with modest sized instruments.

Green and Black Auroras Over Norway
29.03.2006

What causes gaps between aurora curtains? These unusual gaps can make Research using data from four Cluster spacecraft orbiting the Earth has likely found the secret: auroral gaps, sometimes knows as black auroras, are actually anti-auroras. In normal auroras, electrons and/or predominantly negatively charged particles fall toward Earth along surfaces of constant magnetic field.

Bright Cliffs Across Saturns Moon Dione
5.09.2006

What causes the bright streaks on Dione? Recent images of this unusual moon by the robot Cassini spacecraft now orbiting Saturn are helping to crack the mystery. Close inspection of Dione's trailing hemisphere, pictured above, indicates that the white wisps are composed of deep ice cliffs dropping hundreds of meters.

Io: The Prometheus Plume
10.02.2007

What's happening on Jupiter's moon Io? Two sulfurous eruptions are visible on Jupiter's volcanic moon Io in this color composite image from the robotic Galileo spacecraft that orbited Jupiter from 1995 to 2003.