M101: The Pinwheel Galaxy
14.04.2009

Why do many galaxies appear as spirals? A striking example is M101, shown above, whose relatively close distance of about 27 million light years allow it to be studied in some detail. Recent evidence...

Simulating the Universe
8.11.1995

The above cube represents a chunk of our universe as simulated by the Grand Challenge Cosmology Consortium (GC3). The cube is huge - it would take light 500 million years to cross it. Low density gas is shown as blue, and high density gas as red.

M101: The Pinwheel Galaxy
10.03.2003

Why do many galaxies appear as spirals? A striking example is M101, shown above, whose relatively close distance of about 22 million light years allow it to be studied in some detail. Recent evidence...

Saturn from Earth
2.09.1998

Saturn is the second largest planet in our Solar System. Saturn has been easily visible in the sky since history has been recorded. Galileo used one of the first telescopes in 1610 to discover Saturn's rings, which he first thought were moons.

Fire in Space
10.08.2021

What does fire look like in space? In the gravity on Earth, heated air rises and expands, causing flames to be teardrop shaped. In the microgravity of the air-filled International Space Station (ISS), however, flames are spheres.

Stardust in Perseus
29.11.2007

This cosmic expanse of dust, gas, and stars covers some 4 degrees on the sky in the heroic constellation Perseus. Centered in the gorgeous skyscape is the dusty blue reflection nebula NGC 1333, about 1,000 light-years away. At that estimated distance, the field of view is nearly 70 light-years across.

Airglow Ripples over Tibet
1.09.2014

Why would the sky look like a giant target? Airglow. Following a giant thunderstorm over Bangladesh in late April, giant circular ripples of glowing air appeared over Tibet, China, as pictured above. The unusual...

Open Star Cluster M38
7.01.2003

Open cluster M38 can be seen with binoculars toward the constellation of Auriga. M38 is considered an intermediately rich open cluster of stars, each of which is about 200 million years old. Located...

Edmund Halley's Greatest Discoveries
6.07.1996

Sir Edmond Halley was quite a discoverer. Born in 1656, he computed in 1705 that a bright comet was periodic and would make another appearance in 1758. The comet appeared as predicted and is now known as Comet Halley. Unfortunately, Halley died in 1742 and never saw his prediction come true.

NGC 6357: The Lobster Nebula
28.10.2020

Why is the Lobster Nebula forming some of the most massive stars known? No one is yet sure. Cataloged as NGC 6357, the Lobster Nebula houses the open star cluster Pismis 24 near its center -- a home to unusually bright and massive stars.