Anemic Spiral NGC 4921 from Hubble
15.05.2019

How far away is spiral galaxy NGC 4921? It's surpringly important to know. Although presently estimated to be about 300 million light years distant, a more precise determination could be coupled with its known recession speed to help humanity better calibrate the expansion rate of the entire visible universe.

GLAST Gamma Ray Sky Simulation
22.07.2000

What shines in the gamma-ray sky? This simulated image models the intensities of gamma rays with over 40 million times the energy of visible light, and represents how the sky might appear to the Gamma-ray Large Area Space Telescope (GLAST) after its first year in orbit.

A Total Lunar Eclipse Over Tajikistan
7.11.2022

If the full Moon suddenly faded, what would you see? The answer was recorded in a dramatic time lapse video taken during the total lunar eclipse in 2011 from Tajikistan. During a total lunar eclipse, the Earth moves between the Moon and the Sun, causing the moon to fade dramatically.

Fermi's First Light
28.08.2008

Launched on June 11 to explore the universe at extreme energies, the Gamma-ray Large Area Space Telescope has been officially renamed the Fermi Gamma-ray Space Telescope, in honor of Nobel Laureate Enrico Fermi (1901-1954), pioneer in high-energy physics.

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.

M51: Tidal Streams and H-alpha Ciffs
13.12.2024

An intriguing pair of interacting galaxies, M51 is the 51st entry in Charles Messier's famous catalog. Perhaps the original spiral nebula, the large galaxy with whirlpool-like spiral structure seen nearly face-on is also cataloged as NGC 5194. Its spiral arms and dust lanes sweep in front of its smaller companion galaxy, NGC 5195.

38 Hours in the M81 Group
10.04.2025

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.

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.

The Densest Galaxy
4.10.2013

The bright core and outer reaches of giant elliptical galaxy M60 (NGC 4649) loom large at the upper left of this sharp close-up from the Hubble Space Telescope. Some 54 million light-years away and 120,000 light-years across, M60 is one of the largest galaxies in the nearby Virgo Cluster.

The Dark River to Antares
16.05.2020

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.