The 100 Meter Green Bank Radio Telescope
11.03.2002

The largest single-dish fully steerable radio telescope began operation in 2000 August in Green Bank, West Virginia, USA. Dedicated as the Robert C. Byrd Green Bank Telescope, the device weighs over 30 times more than the Statue of Liberty, and yet can point anywhere in the sky more precisely than one thousandth of a degree.

Leonids Over Monument Valley
19.11.2012

What's happening in the sky over Monument Valley? A meteor shower. Over the past weekend the Leonid meteor shower has been peaking. The image -- actually a composite of six exposures of about 30 seconds each -- was taken in 2001, a year when there was a much more active Leonids shower.

Roque de los Muchachos Observatory
19.08.2002

Above the clouds, atop an island off the coast of Africa, a group of cutting-edge telescopes inspects the universe. Pictured above are telescopes at Roque de los Muchachos Observatory on La Palma, one of the Canary Islands, Spain. The site is one of the premier observing locations on Earth.

Perseid over Albrechtsberg Castle
9.08.2013

Medieval Albrechtsberg castle is nestled in trees near the northern bank of the river Pielach and the town of Melk, Austria. In clearing night skies on August 12, 2012 it stood under constellations of the northern summer, including Aquarius, Aquila, and faint, compact Delphinus (above and right of center) in this west-looking skyview.

The Largest Impact Crater
6.09.1996

What is the largest known impact crater in the Solar System? Over 1300 miles across, the South Pole-Aitken Basin on the farside of Earth's Moon holds that distinction. Circled above in a false color mosaic of Clementine images it was caused when an asteroid or comet sized object crashed

A Perseid Aurora
9.08.2003

Just after the Moon set but before the Sun rose in the early morning hours of 2000 August 12, meteors pelted the Earth from the direction of the constellation Perseus, while ions pelted the Earth from the Sun.

Meteor by Moonlight
15.08.2009

Dark skies are favored for viewing meteor showers. But the annual Perseid Meteor Shower still entertained skygazers around the world this week even though the Moon brightened the night. At its last quarter phase...

The McMath-Pierce Solar Observatory
15.03.1996

This odd-looking structure silhouetted in the foreground houses the three largest solar telescopes in the world. Located in Kitt Peak, Arizona, the largest telescope inside the McMath-Pierce Facility is 1.6-meters in diameter and contains only mirrors. The telescope contains no windows or lenses because focusing bright sunlight would overheat them.

Debris Disks Surround Distant Suns
10.12.2004

In this dramatic artist's vision, debris along the outer reaches of a planet forming disk orbits in the glare of a distant sun. But inset are actual images of such disks around two nearby stars - AU Microscopii (top left; edge-on) and HD107146 (right: face-on) - as seen by the Hubble Space Telescope.

Milky Way over Bosque Alegre Station in Argentina
22.09.2015

What are those streaks of light in the sky? First and foremost, the arching structure is the central band of our Milky Way galaxy. Visible in this galactic band are millions of distant stars mixed with numerous lanes of dark dust.