Kepler's Supernova Remnant in X Rays
15.05.2013

What caused this mess? Some type of star exploded to create the unusually shaped nebula known as Kepler's supernova remnant, but which type? Light from the stellar explosion that created this energized cosmic cloud was first seen on planet Earth in October 1604, a mere four hundred years ago.

38 Hours in the M81 Group
9.04.2025

From a garden on planet Earth, 38 hours of exposure with a camera and small telescope produced this cosmic photo of the M81 galaxy group. In fact, the group's dominant galaxy M81 is near the center of the frame sporting grand spiral arms and a bright yellow core.

Young Star Cluster NGC 346
1.05.2025

The most massive young star cluster in the Small Magellanic Cloud is NGC 346, embedded in our small satellite galaxy's largest star forming region some 210,000 light-years distant. Of course the massive stars of NGC 346 are short lived, but very energetic.

COMPTEL Explores The Radioactive Sky
24.07.1996

Diffuse gas clouds laced with radioactive aluminum atoms (Al26) line the plane of our Milky Way Galaxy! How do we see them? Relying on the Compton Effect, the COMPTEL instrument onboard NASA's immense orbiting Compton Gamma Ray Observatory can "see" the 1.8 million electron Volt gamma rays emitted by the radioactive decay.

Unexpected X Rays from Perseus Galaxy Cluster
1.01.2018

Why does the Perseus galaxy cluster shine so strangely in one specific color of X-rays? No one is sure, but a much-debated hypothesis holds that these X-rays are a clue to the long-sought identity of dark matter.

Red Moon, Green Beam
18.04.2014

This is not a scene from a sci-fi special effects movie. The green beam of light and red lunar disk are real enough, captured in the early morning hours of April 15. Of course, the reddened lunar disk is easy to explain as the image was taken during this week's total lunar eclipse.

The Dark River to Antares
15.05.2020

A dark river seems to flow through this sky from the horizon toward colorful clouds near red giant star Antares. Murky looking, the dark river is a dusty nebula obscuring background starlight near the central Milky Way, although the dark dust nebula contains mostly hydrogen molecular gas.

Young Star Cluster NGC 346
12.01.2023

The most massive young star cluster in the Small Magellanic Cloud is NGC 346, embedded in our small satellite galaxy's largest star forming region some 210,000 light-years distant. Of course the massive stars of NGC 346 are short lived, but very energetic.

New Moons For Saturn
2.11.2000

Which planet has the most moons? For now, it's Saturn. Four newly discovered satellites bring the ringed planet's total to twenty-two, just edging out Uranus' twenty-one for the most known moons in the solar system. Of course, the newfound Saturnian satellites are not large and photogenic.

Gamma Ray Earth and Sky
6.12.2013

For an Earth-orbiting gamma-ray telescope, Earth is actually the brightest source of gamma-rays, the most energetic form of light. Gamma-rays from Earth are produced when high energy particles, cosmic rays from space, crash into the atmosphere.