The M7 Open Star Cluster in Scorpius
5.04.2000

M7 is one of the most prominent open clusters of stars on the sky. The cluster, dominated by bright blue stars, can be seen with the naked eye in a dark sky in the tail of the constellation of Scorpius.

The Magnificent Tail of Comet McNaught
5.12.2009

Comet McNaught, the Great Comet of 2007, was the brightest comet of the last 40 years. Its spectacular tail spread across the sky and was breathtaking to behold from dark locations for many Southern Hemisphere observers.

Sunset, Shadowrise
29.07.2010

From central Australia, this serene 360 degree panorama follows a clear horizon as twilight began on May 28. At left, a bright western sky is still illuminated by the setting Sun. But sweeping right...

IC 1396: Emission Nebula in Cepheus
5.08.2012

Stunning emission nebula IC 1396 mixes glowing cosmic gas and dark dust clouds in the high and far off constellation of Cepheus. Energized by the bright, bluish central star seen here, this star forming region sprawls across hundreds of light-years -- spanning over three degrees on the sky while nearly 3,000 light-years from planet Earth.

Sunspot Group AR 2192 Crackles
22.10.2014

One of the largest sunspot groups in recent years is now crossing the Sun. Labelled Active Region 2192, it has already thrown a powerful solar flare and has the potential to produce more.

Great Refractor and Lunar Eclipse
25.11.2021

Rain clouds passed and the dome of the Lick Observatory's 36 inch Great Refractor opened on November 19. The historic telescope was pointed toward a partially eclipsed Moon. Illuminated by dim red lighting...

Io's Shadow
7.10.1996

Caught in the act earlier this summer by the Hubble Space Telescope, the volcanic moon Io (above and right of center) and its shadow (black dot) are seen here against Jupiter's clouds.

The Center of the Circinus Galaxy in X Rays
16.05.2001

Are black holes the cause of X-rays that pour out from the center of the Circinus galaxy? A new high-resolution image from the orbiting Chandra X-ray Observatory has resolved the inner regions of this nearby galaxy into several smaller sources. The image is shown above in representative-color.

Tycho Brahe Measures the Sky
15.09.1996

Tycho Brahe was the most meticulous astronomical observer of his time. Brahe, who lived between 1546 and 1601, set out to solve the day's most pressing astronomical problem: to determine whether the Earth or the Sun was at the center of the Solar System.

The Solar Spectrum
29.06.2003

It is still not known why the Sun's light is missing some colors. Shown above are all the visible colors of the Sun, produced by passing the Sun's light through a prism-like device.