APOD: 2026 April 4 Б Hello World
4.04.2026

From pole to pole our fair planet is captured in this snapshot from space, an evocative image from a window of the Orion spacecraft Integrity. From the spacecraft's perspective the Sun is moving behind Earth's bright limb along the lower right.

Red Saturn
10.02.2005

This strange, false-color image of otherwise familiar planet Saturn shows temperature changes based on thermal infrared emission in the gas giant's atmosphere and rings. Recorded from the Keck I telescope on Mauna Kea, the sharp, ground-based picture of Saturn's southern hemisphere is a mosaic of 35 images.

Unusual Aurora During Solar Wind Dropout
23.12.1999

On May 10, for some unknown reason, the Solar Wind virtually stopped. Normally our Sun emits a wind of between five and ten energetic particles per cubic centimeter moving outward at about 500 kilometers per second.

Star Trails for a Red Planet
30.11.2019

Does Mars have a north star? In long exposures of Earth's night sky, star trails make concentric arcs around the north celestial pole, the direction of our fair planet's axis of rotation. Bright star Polaris is presently the Earth's North Star, close on the sky to Earth's north celestial pole.

Saturns Hexagon Comes to Light
22.01.2012

Believe it or not, this is the North Pole of Saturn. It is unclear how an unusual hexagonal cloud system that surrounds Saturn's north pole was created, keeps its shape, or how long it will last.

Saturns Hexagon Comes to Light
14.12.2009

Believe it or not, this is the North Pole of Saturn. It is unclear how an unusual hexagonal cloud system that surrounds Saturn's north pole was created, keeps its shape, or how long it will last.

A Mysterious Hexagonal Cloud System on Saturn
3.04.2007

Why would clouds form a hexagon on Saturn? Nobody is yet sure. Originally discovered during the Voyager flybys of Saturn in the 1980s, nobody has ever seen anything like it anywhere else in the Solar System.

Circumpolar Star Trails
18.01.2019

As Earth spins on its axis, the stars appear to rotate around an observatory in this well-composed image from the Canary Island of Tenerife. Of course, the colorful concentric arcs traced out by the stars are really centered on the planet's North Celestial Pole.

Little Planet Lookout
9.11.2018

Don't panic. This little planet projection looks confusing, but it's actually just a digitally warped and stitched, nadir centered mosaic of images that covers nearly 360x180 degrees. The images were taken on the night of October 31 from a 30 meter tall hill-top lookout tower near Tatabanya, Hungary, planet Earth.

When Vega is North
8.05.2015

In only about 12,000 years Vega will be the North Star, the closest bright star to our fair planet's North Celestial Pole. By then, when you fix your camera to a tripod...