The Bubble
16.07.2004

Blown by the wind from a star, this tantalizing, ghostly apparition is cataloged as NGC 7635, but known simply as The Bubble Nebula. Astronomer Ken Crawford's striking view combines a long exposure through a hydrogen alpha filter with color images to reveal the intricate details of this cosmic bubble and its environment.

The Colors of IC 1795
10.12.2009

This colorful cosmic portrait features glowing gas and dark dust clouds in IC 1795, a star forming region in the northern constellation Cassiopeia. The nebula's colors were created by adopting the Hubble false-color...

NGC 6823: Cloud Sculpting Star Cluster
8.10.2014

Star cluster NGC 6823 is slowly turning gas clouds into stars. The center of the open cluster, visible on the upper right, formed only about two million years ago and is dominated in brightness by a host of bright young blue stars.

Carina over Lake Ballard
5.01.2018

A jewel of the southern sky, the Great Carina Nebula, also known as NGC 3372, is one of our galaxy's largest star forming regions. Easily visible to the unaided eye it stands high...

Messier 20 and 21
24.08.2018

The beautiful Trifid Nebula, also known as Messier 20, is easy to find with a small telescope in the nebula rich constellation Sagittarius. About 5,000 light-years away, the colorful study in cosmic contrasts shares this well-composed, nearly 1 degree wide field with open star cluster Messier 21 (bottom right).

N44C: A Nebular Mystery
14.05.2002

Why is N44C glowing so strangely? The star that appears to powers the nebula, although young and bright, does not seem hot enough to create some of the colors observed. A search for a hidden hotter star in X-rays has come up empty.

NGC 7129 and NGC 7142
30.08.2019

This wide-field telescopic image looks toward the constellation Cepheus and an intriguing visual pairing of dusty reflection nebula NGC 7129 (right) and open star cluster NGC 7142. The two appear separated by only half a degree on the sky, but they actually lie at quite different distances.

APOD: 2024 June 11 Б Colorful Stars and Clouds near Rho Ophiuchi
11.06.2024

Why is the sky near Antares and Rho Ophiuchi so colorful, yet dusty? The colors result from a mixture of objects and processes. Fine dust -- illuminated by starlight -- produces blue reflection nebulae. Gaseous clouds whose atoms are excited by ultraviolet starlight produce reddish emission nebulae. Backlit dust clouds block starlight and so appear dark.

The Southern Sky in Warm Hydrogen
29.01.2002

A robotic telescope with red sunglasses in Chile has been photographing the entire southern sky for years. The result, shown above, is the most complete sky map of the most common visible light emitted from the most abundant element in our Galaxy: hydrogen. A very specific red color emitted by warm ionized hydrogen was observed.

A Spectre in the Eastern Veil
1.11.2008

Menacing flying forms and garish colors are a mark of the Halloween season. They also stand out in this cosmic close-up of the eastern Veil Nebula. The Veil Nebula itself is a large supernova remnant, the expanding debris cloud from the death explosion of a massive star.