X Rays from the Perseus Cluster Core
8.12.2005

The Perseus Cluster of thousands of galaxies, 250 million light-years distant, is one of the most massive objects in the Universe and the brightest galaxy cluster in the x-ray sky. At its core lies the giant cannibal galaxy Perseus A (NGC 1275), accreting matter as gas and galaxies fall into it.

Simeis 147: Supernova Remnant
9.10.2012

It's easy to get lost following the intricate filaments in this detailed mosaic image of faint supernova remnant Simeis 147 (S147). Also cataloged as Sh2-240, it covers nearly 3 degrees or 6 full moons on the sky. That's about 150 light-years at the stellar debris cloud's estimated distance of 3,000 light-years.

Mira: The Wonderful Star
5.05.2005

To seventeenth century astronomers, Omicron Ceti or Mira was known as a wonderful star - a star whose brightness could change dramatically in the course of about 11 months. Modern astronomers now recognize an entire class of long period Mira-type variables as cool, pulsating, red giant stars, 700 or so times the diameter of the Sun.

Building Galaxies in the Early Universe
10.09.2007

What was the very early universe like? To help find out, astronomers pointed the Hubble Space Telescope between bright nearby objects to create one of the deepest images ever -- the Hubble Ultra Deep Field (HUDF). The resulting HUDF is like a jewel box of strange and distant galaxies.

IC 4603: Reflection Nebula in Ophiuchius
23.07.2014

Why does this starfield photograph resemble an impressionistic painting? The effect is created not by digital trickery but by large amounts of interstellar dust. Dust, minute globs rich in carbon and similar in size to cigarette smoke, frequently starts in the outer atmospheres of large, cool, young stars.

A Scorpius Sky Spectacular
4.05.2014

If Scorpius looked this good to the unaided eye, humans might remember it better. Scorpius more typically appears as a few bright stars in a well-known but rarely pointed out zodiacal constellation. To get a spectacular image like this, though, one needs a good camera, color filters, and a digital image processor.

The W in Cassiopeia
18.03.2016

A familiar, zigzag, W pattern in northern constellation Cassiopeia is traced by five bright stars in this colorful and broad mosaic. Stretching about 15 degrees across rich starfields, the celestial scene includes dark clouds, bright nebulae, and star clusters along the Milky Way. In yellow-orange hues Cassiopeia's alpha star Shedar is a standout though.

Fox Fur, a Unicorn, and a Christmas Tree
24.12.2016

Clouds of glowing hydrogen gas fill this colorful skyscape in the faint but fanciful constellation Monoceros, the Unicorn. A star forming region cataloged as NGC 2264, the complex jumble of cosmic gas and dust...

The Tarantula Nebula
16.11.2017

The Tarantula Nebula is more than a thousand light-years in diameter, a giant star forming region within nearby satellite galaxy the Large Magellanic Cloud, about 180 thousand light-years away. The largest, most violent star...

Fox Fur, Unicorn, and Christmas Tree
7.02.2019

Clouds of glowing hydrogen gas fill this colorful skyscape in the faint but fanciful constellation Monoceros, the Unicorn. A star forming region cataloged as NGC 2264, the complex jumble of cosmic gas and dust...