Dark Sand Cascades on Mars
28.11.2015

They might look like trees on Mars, but they're not. Groups of dark brown streaks have been photographed by the Mars Reconnaissance Orbiter on melting pinkish sand dunes covered with light frost. The above image was taken in 2008 April near the North Pole of Mars.

UGC 12591: The Fastest Rotating Galaxy Known
6.03.2017

Why does this galaxy spin so fast? To start, even identifying which type of galaxy UGC 12591 is difficult -- it has dark dust lanes like a spiral galaxy but a large diffuse bulge of stars like a lenticular.

Milky Way over Deadvlei in Namibia
17.04.2018

What planet is this? It is the only planet currently known to have trees. The trees in Deadvlei, though, have been dead for over 500 years. Located in Namib-Naukluft Park in Namibia (Earth), saplings grew after rainfall caused a local river to overflow, but died after sand dunes shifted to section off the river.

Red Sprite Lightning over Kununurra
24.02.2019

What are those red filaments in the sky? It is a rarely seen form of lightning confirmed only about 30 years ago: red sprites. Recent research has shown that following a powerful positive cloud-to-ground...

Moon over Andromeda
24.09.2020

The Great Spiral Galaxy in Andromeda (also known as M31), a mere 2.5 million light-years distant, is the closest large spiral to our own Milky Way. Andromeda is visible to the unaided...

SOFIA s Southern Lights
28.07.2022

SOFIA, the Stratospheric Observatory for Infrared Astronomy, is a Boeing 747SP aircraft modified to carry a large reflecting telescope into the stratosphere. The ability of the airborne facility to climb above about 99 percent of Earth's infrared-blocking atmosphere has allowed researchers to observe from almost anywhere over the planet.

APOD: 2023 October 15 Б An Eclipse Tree
14.10.2023

Yes, but can your tree do this? If you look closely at the ground in the featured image, you will see many images of yesterday's solar eclipse -- created by a tree. Gaps between...

APOD: 2026 June 2 Б The Vela Supernova Remnant
1.06.2026

The explosion is over, but the consequences continue. About twelve thousand years ago, a relatively normal star in the constellation Vela suddenly exploded, creating a strange point of light briefly visible to humans living near the beginning of recorded history.

The Deep Field
23.01.1996

The image above is part of the Hubble Deep Field and represents humanity's most distant yet optical view of the Universe. Galaxies like colorful pieces of candy fill the field, some as faint as 30th magnitude (about four billion times fainter than stars visible to the unaided eye).

Comet Halley's Nucleus
9.12.1996

Here is what a comet nucleus really looks like. For all active comets except Halley, it was only possible to see the surrounding opaque gas cloud called the coma. During Comet Halley's most...