Pyrenees Paraselene
11.06.2009

A sea of clouds laps at rugged moutain peaks of the French Pyrenees in this serene view from Pic du Midi Observatory. The time exposure was recorded on June 4, with the constellations Sagittarius and Scorpius shining in the starry night. At the top right lies a faint, but colorful moondog or paraselene.

Lightning on Earth
18.08.2004

Nobody knows what causes lightning. It is known that charges slowly separate in some clouds causing rapid electrical discharges (lightning), but how electrical charges get separated in clouds remains a topic of much research.

M13: The Great Globular Cluster in Hercules
1.03.2000

M13 is one of the most prominent and best known globular clusters. Visible with binoculars in the constellation of Hercules, M13 is frequently one of the first objects found by curious sky gazers seeking celestials wonders beyond normal human vision.

A Leonid Bolide Over Kansas
25.11.1998

The 1998 Leonid Meteor Shower featured many bright events. Extremely bright meteors, known as bolides or fireballs, can briefly glow brighter than the full moon. Pictured above is a Leonid bolide caught during a five-minute, wide-angle exposure. The bolide was so bright it lit up the surrounding area, making otherwise dark trees visible.

M13: A Great Globular Cluster of Stars
17.06.2009

M13 is one of the most prominent and best known globular clusters. Visible with binoculars in the constellation of Hercules, M13 is frequently one of the first objects found by curious sky gazers seeking celestials wonders beyond normal human vision.

The X-Ray Moon
29.09.1996

This X-Ray image of the Moon was made by the orbiting Roentgen Observatory Satellite (ROSAT) in 1990. It shows three distinct regions: a bright X-ray sky, a bright part of the Moon, and a relatively dark part of the Moon. The bright X-ray sky is due to the diffuse cosmic X-ray background.

Irregular Galaxy Sextans A
18.12.1999

Grand spiral galaxies often seem to get all the glory. Their newly formed, bright, blue star clusters found along beautiful, symmetric spiral arms are guaranteed to attract attention. But small irregular galaxies form stars too, like this lovely, gumdrop-shaped galaxy, Sextans A.

Escape From The Sun
20.11.1997

Twisted magnetic fields arching from the solar surface can trap ionized gas, suspending it in huge looping structures. These majestic plasma arches are seen as prominences above the solar limb. On September 14, this...

Colors of Comet Pojmanski
11.03.2006

Comet Pojmanski flew by planet Earth last weekend on a surprise trip through the inner solar system. Then an easy binocular target for morning skygazers, Pojmanski ultimately showed off a long tail, but it also presented some lovely green-blue hues as gas molecules in its tenuous coma and tail fluoresced in the sunlight.

Deploying Spartan
12.08.1999

Last October the Space Shuttle Discovery deployed Spartan 201, a spacecraft that monitored the corona of the Sun. Instruments on Spartan 201 were used to estimate the density of electrons emitted into the solar...