APOD: 2025 March 23 Б Ancient Ogunquit Beach on Mars
23.03.2025

This was once a beach -- on ancient Mars. The featured 360-degree panorama, horizontally compressed, was taken in 2017 by the robotic Curiosity rover that explored the red planet. Named Ogunquit Beach after its terrestrial...

A Massive Cluster In A Young Universe
21.08.1998

Conventional theories suggest that this cluster of galaxies should not exist. Each fuzzy spot in this false-color Hubble Space Telescope image of the central regions of a newly discovered galaxy cluster is a galaxy similar in mass to our own Milky Way.

Fractal Interstellar Dust Up Close
9.05.1999

Our universe is a very dusty place. Dust usually shows its presence by blocking out light emitted from stars or nebulae behind it, sometimes creating the illusion of a horse's head or a sombrero hat. But nobody really knows what a typical interstellar dust grain looks like. By

In the Vicinity of the Cone Nebula
12.05.2003

Strange shapes and textures can be found in neighborhood of the Cone Nebula. The unusual shapes originate from fine interstellar dust reacting in complex ways with the energetic light and hot gas being expelled by the young stars.

Martian Moon Phobos from MGS
1.07.2003

Why is Phobos so dark? Phobos, the largest and innermost of two Martian moons, is the darkest moon in the entire Solar System. Its unusual orbit and color indicate that it may be a captured asteroid composed of a mixture of ice and dark rock.

NGC 3621: Far Beyond the Local Group
19.07.2003

Far beyond the local group of galaxies lies NGC 3621, some 22 million light-years away. Found in the serpentine southern constellation Hydra, the loose spiral arms of this gorgeous island universe are loaded with luminous young star clusters and dark dust lanes.

Orion's Horsehead Nebula
25.10.1997

The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the black indentation to the red emission nebula seen just to the right of center of the above photograph. The bright star near the center is located in the belt of the familiar constellation of Orion.

The N44 Superbubble
6.02.2006

What created this gigantic hole? The vast emission nebula N44 in our neighboring galaxy the Large Magellanic Cloud has a large, 250 light-year hole and astronomers are trying to figure out why. One possibility is particle winds expelled by massive stars in the bubble's interior that are pushing out the glowing gas.

The Rosette Nebula in Hydrogen, Oxygen, and Sulfur
11.01.2000

The Rosette Nebula is a large emission nebula located 3000 light-years away. The great abundance of hydrogen gas gives NGC 2237 its red color in most photographs. The wind from the open cluster of stars known as NGC 2244 has cleared a hole in the nebula's center.

The Magnificent Horsehead Nebula
13.05.2010

Sculpted by stellar winds and radiation, a magnificent interstellar dust cloud by chance has assumed this recognizable shape. Fittingly named the Horsehead Nebula, it is some 1,500 light-years distant, embedded in the vast Orion cloud complex.