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.

September Sky
29.09.2000

Star clusters, planets, and a red giant posed for this portrait of the night sky from rural Jasper County, Iowa, USA. Astrophotographer Stan Richard recorded the four minute time exposure looking east around midnight on September 3rd at Ashton-Wildwood Park.

Double Asteroid 90 Antiope
1.11.2000

This eight-frame animation is based on the first ever images of a double asteroid! Formerly thought to be a single enormous chunk of rock, asteroid 90 Antiope resides in the solar system's main asteroid belt between Mars and Jupiter.

BATSE GRB Final Sky Map
28.06.2000

What causes the most powerful explosions in the universe? The BATSE modules that flew on the Compton Gamma Ray Observatory allowed more insight into enigmatic gamma-ray burst (GRB) explosions than ever before. From 1991-2000, BATSE detected 2704 GRBs, much more than ever previously recorded.

Tails Of Comet LINEAR
27.07.2000

Comet C/1999 S4 LINEAR is only one of many comets discovered with the Lincoln Near Earth Asteroid Research (LINEAR) telescope operating near Soccoro, New Mexico, USA. Traveling steadily southward through Earth's night...

Betelgeuse Resolved
5.08.2009

The sharpest image ever of Betelgeuse shows a mammoth star that is slowly evaporating. Betelgeuse (sounds a lot like "beetle juice"), also known as Alpha Orionis, is one of the largest and brightest stars known. The star is a familiar orange fixture easily visible to the unaided eye toward the constellation of Orion.

Unusual Mountain Ahuna Mons on Asteroid Ceres
9.10.2017

What created this unusual mountain? Ahuna Mons is the largest mountain on the largest known asteroid in our Solar System, Ceres, which orbits our Sun in the main asteroid belt between Mars and Jupiter. Ahuna Mons, though, is like nothing that humanity has ever seen before.

Evidence of an Active Volcano on Venus
14.01.2020

Are volcanoes still active on Venus? More volcanoes are known on Venus than Earth, but when Venusian volcanoes last erupted is not directly known. Evidence bolstering very recent volcanism on Venus has recently been uncovered, though, right here on Earth.

Stereo Mars
3.12.2022

Mars looks sharp in these two rooftop telescope views captured in late November from Singapore, planet Earth. At the time, Mars was about 82 million kilometers from Singapore and approaching its opposition, opposite the Sun in planet Earth's sky on December 8.

APOD: 2025 March 12 Б NGC 772: The Fiddlehead Galaxy
12.03.2025

Why does this galaxy look like a curly vegetable? The Fiddlehead spiral galaxy likely gets its distorted spiral appearance from a gravitational interaction with its close-by elliptical companion NGC 770, seen just below. Cataloged...