Saturns Hyperion: A Moon with Odd Craters
3.10.2005

What lies at the bottom of Hyperion's strange craters? Nobody knows. To help find out, the robot Cassini spacecraft now orbiting Saturn swooped past the sponge-textured moon again last week and took an image of unprecedented detail.

An Intermediate Polar Binary System
21.05.2006

How can two stars create such a strange and intricate structure? Most stars are members of multiple-star systems. Some stars are members of close binary systems where material from one star swirls around the other in an accretion disk.

Tropic of Cancer
2.08.2013

This intriguing monument can be found in Taiwan between the cities of Hualian and Taitong. Split into two sides, it straddles a special circle of latitude on planet Earth, near 23.5 degrees north, known as the Tropic of Cancer.

Approaching Asteroid Ceres
19.01.2015

It is the largest asteroid in the asteroid belt -- what secrets does it hold? To find out, NASA has sent the robotic Dawn spacecraft to explore and map this cryptic 1,000-kilometer wide world: Ceres. Orbiting between Mars and Jupiter, Ceres is officially categorized as a dwarf planet but has never been imaged in detail.

The Winds of Earth
10.10.2016

Which way is the wind blowing? The featured map can tell you this and much more, no matter your location on planet Earth. The dynamic map displays supercomputer forecasts drawn from multiple sources of global satellite data updated every three hours.

Neptune's Great Dark Spot: Gone But Not Forgotten
1.12.2001

When NASA's Voyager 2 spacecraft flew by distant Neptune in August of 1989, astronomers were shocked. Since Neptune receives only 3 percent the sunlight Jupiter does, they expected to find a dormant, dark, frigid planet. Instead, the Voyager images revealed evidence of a dynamic and turbulent world.

Vela Supernova Remnant in Visible Light
13.02.2007

The explosion is over but the consequences continue. About eleven thousand years ago a star in the constellation of Vela could be seen to explode, creating a strange point of light briefly visible to humans living near the beginning of recorded history.

Analemma Over the Porch of Maidens
21.12.2008

If you took a picture of the Sun at the same time each day, would it remain in the same position? The answer is no, and the shape traced out by the Sun over the course of a year is called an analemma.

APOD: 2024 April 8 Б The Changing Ion Tail of Comet Pons Brooks
8.04.2024

How does a comet tail change? It depends on the comet. The ion tail of Comet 12P/PonsБBrooks has been changing markedly, as detailed in the featured image sequenced over nine days from March 6 to 14 (top to bottom).

The Shadow of Phobos
29.03.2003

Hurtling through space above the Red Planet, potato-shaped Phobos completes an orbit of Mars in less than eight hours. In fact, since its orbital period is shorter than the planet's rotation period, Mars-based...