HCG 87: A Small Group of Galaxies
6.09.1999

Sometimes galaxies form groups. For example, our own Milky Way Galaxy is part of the Local Group of Galaxies. Small, compact groups, like Hickson Compact Group 87 (HCG 87) shown above, are interesting partly because they slowly self-destruct.

Saturn s Ancient Rings
16.12.2007

How old are Saturn's rings? No one is quite sure. One possibility is that the rings formed relatively recently in our Solar System's history, perhaps only about 100 million years ago when a moon-sized object broke up near Saturn.

The Local Fluff
24.09.2013

The stars are not alone. In the disk of our Milky Way Galaxy about 10 percent of visible matter is in the form of gas, called the interstellar medium (ISM). The ISM is not uniform, and shows patchiness even near our Sun.

X Ray Milky Way
12.07.2003

If you had x-ray vision, the center regions of our Galaxy would not be hidden from view by the immense cosmic dust clouds opaque to visible light. Instead, the Milky Way toward Sagittarius might look something like this stunning mosaic of images from the orbiting Chandra Observatory.

The Lonely Neutron Star in Supernova E0102 72.3
29.09.2018

Why is this neutron star off-center? Recently a lone neutron star has been found within the debris left over from an old supernova explosion. The "lonely neutron star" in question is the blue dot at the center of the red nebula near the bottom left of E0102-72

HESS Telescopes Explore the High Energy Sky
7.01.2019

They may look like modern mechanical dinosaurs but they are enormous swiveling eyes that watch the sky. The High Energy Stereoscopic System (H.E.S.S.) Observatory is composed of four 12-meter reflecting-mirror telescopes surrounding a larger telescope housing a 28-meter mirror.

X rays From HCG 62
8.03.2001

Scanning the skies for galaxies Canadian astronomer Paul Hickson and colleagues identified some 100 compact groups of galaxies, now appropriately called Hickson Compact Groups (HCGs). With only a few member galaxies per group, HCGs...

Lunar Prospects
18.09.1998

Launched on January 6th, NASA's Lunar Prospector spacecraft has been exploring the Moon with instruments designed to sense global properties while orbiting pole-to-pole, 63 miles above the lunar surface. Now over half...

Recurrent Nova RS Ophiuci
23.02.2006

This pretty star field in the constellation Ophiucus is centered on a star not often seen - RS Ophiuci. In fact, early last week RS Oph suddenly became visible to the naked eye for the first time since 1985.

Gamma Ray Bursting
3.11.1999

Using graphics and data from NASA's Compton Gamma Ray Observatory, this animation illustrates one of the most exciting mysteries of modern astrophysics, gamma-ray bursts. Incredibly gamma-ray bursts, sudden flashes of radiation with over 100,000 times the energy of visible light photons, occur several times a day.