Astronomy Picture Of the Day (APOD)Metal on the Plains of Mars
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 during descent.
A Tale of Two Hemispheres
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 south's high Atacama Desert between the two hemispheres of the Milky Way Galaxy.
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 (3 miles) above the crater floor.
NGC 6188 and NGC 6164
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.
Introducing Comet Garradd
Another large snowball is falling toward the Sun. Comet Garradd was discovered two years ago by Gordon Garradd in Australia, and is currently visible through a small telescope at visual magnitude nine. Officially designated...
Galaxy NGC 474: Cosmic Blender
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...
Milky Way Over Abandoned Kilns
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 abandon due to a town fire and flooding, but remain in good condition even today.
A Flight of Helios
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, the remotely piloted Helios is traveling at about 40 kilometers per hour.
NGC 2403 in Camelopardalis
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 share of giant star forming HII regions, marked by the telltale reddish glow of atomic hydrogen gas.
Pluto s P4
Nix and Hydra were first introduced to human eyes in Hubble Space Telescope images from May 2005, as Pluto's second and third known moons. Now Hubble images have revealed a fourth satellite for the icy, dwarf planet. Provisionally designated P4, it completes an orbit of Pluto in about 31 days.