Intriguing Dimples Near Eagle Crater on Mars
24.03.2004

What are those unusual looking dimples? Looking back toward Eagle crater, its landing place on Mars, the robot rover Opportunity has spotted some unusual depressions in the Martian soil. The dimples, visible above on the image left, each measure about one meter across and appear to have light colored rock in their interior.

Noctilucent Clouds Over Sweden
28.10.2007

Sometimes it's night on the ground but day in the air. As the Earth rotates to eclipse the Sun, sunset rises up from the ground. Therefore, at sunset on the ground, sunlight still shines on clouds above.

In the Heart of the Tarantula Nebula
31.03.2009

In the heart of monstrous Tarantula Nebula lies huge bubbles of energetic gas, long filaments of dark dust, and unusually massive stars. In the center of this heart, is a knot of stars so dense that it was once thought to be a single star.

An Anomalous SETI Signal
7.03.2004

No one knows for sure what caused this signal. There is a slight possibility that it just might originate from an extraterrestrial intelligence. The bright colors on the blue background indicate that an anomalous signal was received here on Earth by a radio telescope involved in a Search for Extraterrestrial Intelligence (SETI).

APOD: 2023 September 11 Б Beautiful Comet Nishimura
11.09.2023

This scene would be beautiful even without the comet. By itself, the sunrise sky is an elegant deep blue on high, with faint white stars peeking through, while near the horizon is a pleasing tan.

NGC 1316: After Galaxies Collide
22.02.1999

Astronomers turn detectives when trying to figure out the cause of unusual sites like NGC 1316. A preliminary inspection indicates that NGC 1316 is an enormous elliptical galaxy that started devouring a smaller spiral galaxy neighbor about 100 million years ago. Supporting evidence includes the dark dust lanes uniquely indicative of a spiral.

Spiral Meteor through the Heart Nebula
5.09.2016

What is this meteor doing? Dynamically, the unusually short and asymmetric train may indicate that the sand-sized grain at the center of the glow is momentarily spinning as it ablates, causing its path to be slightly spiral.

Block Island Meteorite on Mars
13.08.2009

What is this strange rock on Mars? Sitting on a smooth plane, the rock stands out for its isolation, odd shape, large size and unusual texture. The rock was discovered by the robotic Opportunity rover rolling across Mars late last month. Pictured above, Opportunity prepares to inspect the unusual rock.

GRACE Maps the Gravity of Earth
23.07.2003

Why do some places on Earth have higher gravity than others? Sometimes the reason is unknown. To help better understand the Earth's surface, slight distance changes between a pair of identically orbiting satellites named GRACE have been used to create the best ever map of Earth's gravitational field.

APOD: 2023 May 9 Б Shadows of Earth
9.05.2023

Can you find two Earth shadows in today's image? It's a bit tricky. To find the first shadow, observe that the top part of the atmosphere appears pink and the lower part appears blue. This is because the top half is exposed to direct sunlight, while the lower part is not.