Aurora Iowa
20.05.2005

Early last Sunday morning stars were not the only lights in Iowa skies. The northern lights also shone from the heavens, extending across the midwestern USA and other locations not often graced with auroral displays.

Seven Sisters Versus California
18.06.1996

In the lower left corner, dressed in blue, is the Pleiades. Also known as the Seven Sisters and M45, the Pleiades is one of the brightest and most easily visible open clusters on the sky. The Pleiades contains over 3000 stars, is about 400 light years away, and only 13 light years across.

Seven Sisters Versus California
3.11.2009

On the upper right, dressed in blue, is the Pleiades. Also known as the Seven Sisters and M45, the Pleiades is one of the brightest and most easily visible open clusters on the sky. The Pleiades contains over 3,000 stars, is about 400 light years away, and only 13 light years across.

A Star Forming Region in the LMC
23.08.1997

Stars sometimes form in colorful ways. Pictured above is a small region in the nearby LMC galaxy where stars are forming. After a star is born, it may do several things to energize its immediate neighborhood.

A Star Forming Region in the LMC
25.06.1996

Stars sometimes form in colorful ways. Pictured above is a small region in the nearby LMC galaxy where stars are forming. After a star is born, it may do several things to energize its immediate neighborhood.

Weighing Empty Space
8.07.2002

Sometimes staring into empty space is useful. Pictured above is a region of sky that was picked because it had, well, nothing: no bright stars, no bright galaxies, and no picturesque nebulas. What could not be avoided, however, were a few stars in our own Galaxy, and many distant galaxies strewn across the universe.

V4641 Sgr: The Closest Black Hole Candidate
17.01.2000

An object many astronomers believe is a black hole has been found only 1500 light-years from Earth, making it the closest black hole candidate. Although dramatic explosions emanate from the object, it is far enough away so that we are in no danger.

Galaxies of the Perseus Cluster
8.05.2009

This colorful telescopic skyscape is filled with galaxies that lie nearly 250 million light-years away, the galaxies of the Perseus cluster. Their extended and sometimes surprising shapes are seen beyond a veil of foreground stars in our own Milky Way.

Aurora over Icelandic Fault
30.08.2016

Admire the beauty but fear the beast. The beauty is the aurora overhead, here taking the form of great green spiral, seen between picturesque clouds with the bright Moon to the side and stars in the background. The beast is the wave of charged particles that creates the aurora but might, one day, impair civilization.

Sparkling Star May Indicate Galactic Composition
24.06.1998

If a star in this photograph twinkled slightly, would anyone notice? Would anyone care? Astronomers with the MACHO Collaboration noticed one such twinkle just last week, and many members of the astronomical community now care.