Astronomy Picture of the Day

2011-08-02

Why is the northern half of asteroid Vesta more heavily cratered than the south? No one is yet sure. This unexpected mystery has come to light only in the past few weeks since the robotic Dawn mission became the first spacecraft to orbit the ...

2011-08-01

What's that strange bright streak? It is the last image ever of a space shuttle from orbit. A week and a half ago, after decoupling from the International Space Station, the Space Shuttle Atlantis fired its rockets for the last time, lost its ...

2011-07-31

What has the Opportunity rover found on Mars? While traversing a vast empty plain in 2005 in Meridiani Planum, one of Earth's rolling robots on Mars found a surprise when visiting the location of its own metallic heat shield discarded last year ...

2011-07-30 Tunç Tezel

A quest to find planet Earth's darkest night skies led to this intriguing panorama. In projection, the mosaic view sandwiches the horizons visible in all-sky images taken from the northern hemisphere's Canary Island of La Palma (top) and the ...

2011-07-29

This sharp view from the Thermal Emission Imaging System camera on NASA's Mars Odyssey orbiter is centered on 154 kilometer (96 mile) wide Gale crater, near the martian equator. Within Gale, an impressive layered mountain rises about 5 kilometers ...

2011-07-28 Glittering Lights

Fantastic shapes lurk in clouds of glowing hydrogen gas in NGC 6188. The emission nebula is found near the edge of a large molecular cloud, unseen at visible wavelengths, in the southern constellation Ara, about 4,000 light-years away. Massive, ...

2011-07-26 P.-A. Duc

What's happening to galaxy NGC 474? The multiple layers of emission appear strangely complex and unexpected given the relatively featureless appearance of the elliptical galaxy in less deep images. The cause of the shells is currently unknown, ...

2011-07-25

What's that below the Milky Way? Historic kilns. Built in the 1870s in rural Nevada, USA to process local wood into charcoal, the kilns were soon abandoned due to a town fire and flooding, but remain in good condition even today. The above ...

2011-07-24

An example of solar-powered flight, NASA's Helios aircraft flew almost one hundred years after the Wright brothers' historic flight on December 17, 1903. Pictured here at 3,000 meters in in skies northwest of Kauai, Hawaii, USA in August 2001, ...

2011-07-23

Magnificent island universe NGC 2403 stands within the boundaries of the long-necked constellation Camelopardalis. Some 10 million light-years distant and about 50,000 light-years across, the spiral galaxy also seems to have more than its fair ...