The Lyman Alpha Forest
26.01.2003

We live in a forest. Strewn throughout the universe are "trees" of hydrogen gas that absorb light from distant objects. These gas clouds leave numerous absorption lines in a distant quasar's spectra, together called the Lyman-alpha forest.

Three Planets from Mt Hamilton
30.06.2005

Venus, Mercury, and Saturn wandered close together in western evening skies last week. On Saturnday, June 25, astronomer R. Jay GaBany recorded this snapshot of their eye-catching planetary conjunction, from historic Lick Observatory on Mt. Hamilton, California, USA.

Jupiters Rings Revealed
6.01.2008

Why does Jupiter have rings? Jupiter's rings were discovered in 1979 by the passing Voyager 1 spacecraft, but their origin was a mystery. Data from the Galileo spacecraft that orbited Jupiter from 1995 to 2003 later confirmed that these rings were created by meteoroid impacts on small nearby moons.

NGC 7293: The Helix Nebula
8.01.2011

A mere seven hundred light years from Earth, in the constellation Aquarius, a sun-like star is dying. Its last few thousand years have produced the Helix Nebula (NGC 7293), a well studied and nearby example of a Planetary Nebula, typical of this final phase of stellar evolution.

Laniakea: Our Home Supercluster of Galaxies
10.09.2014

It is not only one of the largest structures known -- it is our home. The just-identified Laniakea Supercluster of galaxies contains thousands of galaxies that includes our Milky Way Galaxy, the Local Group of galaxies, and the entire nearby Virgo Cluster of Galaxies.

NGC 2170: Angel Nebula Still Life
26.08.2019

Is this a painting or a photograph? In this classic celestial still life composed with a cosmic brush, dusty nebula NGC 2170, also known as the Angel Nebula, shines near the image center. Reflecting...

Moon Shadow Moves Over Africa
9.12.2002

When the Moon's shadow reached out and touched the Earth last week, the result was a solar eclipse. Such an eclipse is total only for observers located along a narrow path corresponding to the ground track of the shadow's dark central portion or umbra.

Ghost Galaxy NGC 2915
15.07.1998

How do you find a nearly invisible galaxy? Pictured above is the blue compact dwarf (BCD) galaxy NGC 2915. In visible light, shown above in yellow, this galaxy appears to be a normal dwarf galaxy, as indicated by the yellow smudge in the image center.

Reflections Of Orion
15.01.1999

The Orion Nebula and its surroundings present skygazers with a wondrous jumble of newborn stars, gas, and dust. Emission nebulae - glowing energized clouds of gas, and reflection nebulae - dust clouds shining by reflected starlight, abound at this photogenic cosmic location a mere 1,500 light-years or so away.

Comet Holmes Coma Expands
30.10.2007

Go outside tonight and see Comet Holmes. No binoculars or telescopes are needed -- just curiosity and a sky map. Last week, Comet 17P/Holmes underwent an unusual outburst that vaulted it unexpectedly from obscurity into one of the brightest comets in recent years.