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.

Noctilucent Clouds Over Germany
24.06.2009

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.

Moonrise Through Mauna Keas Shadow
5.12.2010

How can the Moon rise through a mountain? It cannot -- what was photographed here is a moonrise through the shadow of a large volcano. The volcano is Mauna Kea, Hawai'i, USA, a frequent spot for spectacular photographs since it is arguably the premier observing location on planet Earth.

A Cliff Looming on Comet 67P
20.05.2015

What that looming behind this gravel-strewn hill on Comet ChuryumovGerasimenko? A jagged cliff. The unusual double-lobed nucleus of Comet 67P/ChuryumovGerasimenko lends itself to unusual and dramatic vistas, another of which has been captured by the Rosetta spacecraft that arrived at the comet last September.

Aurora over Clouds
24.11.2015

Auroras usually occur high above the clouds. The auroral glow is created when fast-moving particles ejected from the Sun impact the Earth's magnetosphere, from which charged particles spiral along the Earth's magnetic field to strike atoms and molecules high in the Earth's atmosphere.

The Milky Way Over the Arizona Toadstools
22.02.2015

Which is older -- the rocks you see on the ground or the light you see from the sky? Usually its the rocks that are older, with their origin sentiments deposited well before light left any of the stars or nebulas you see in the sky.