SPACE PHOTOS THIS WEEK: Alien Dust, Zodiac Light, More

Zodiacal Light

Photograph courtesy Y. Beletsky, ESO

January 12, 2010—Sunlight reflected off dust between Earth and the sun creates a ghostly white "tent" over the European Southern Observatory's La Silla facility in Chile in September 2009.

The recently released picture, taken minutes after sunset, shows what's known as zodiacal light. This triangular glow appears over the constellations that make up the zodiac, which follow the sun's annual path across the sky, known as the ecliptic. The phenomenon is best viewed in night skies free from light pollution and intense moonlight, such as those over La Silla.

January 12, 2010

Mars Dunes

Image courtesy NASA/JPL/University of Arizona

January 6, 2010—Thawing carbon dioxide ice on Mars causes sand to tumble down dunes in the northern latitudes, leaving dark streaks, as seen in a recently released false-color picture taken by the Mars Reconnaissance Orbiter.

Ice covers these dunes in Martian winter, and the spring thaw causes the ice to sublimate, or turn directly from a solid into a gas. The activity kicks up dark dust and leaves polygonal cracks in the residual ice.

January 12, 2010

Flying Telescope

Photograph courtesy NASA

January 8, 2010—Cruising at 15,000 feet (4,572 meters), NASA's Stratospheric Observatory for Infrared Astronomy, or SOFIA, flew for the first time aboard a modified Boeing 747 with the telescope doors fully opened.

The December 18, 2009, test flight allowed project managers to see if opening the doors affected the plane's handling, disrupted the telescope, or caused anything inside the craft to shake loose. "Everything went well," SOFIA program manager Bob Meyer said in a statement released last week.

SOFIA's 98-inch telescope is designed to collect infrared light from a variety of astronomical objects while soaring at 40,000 feet (12,192 meters). This unique position will help astronomers study objects that are impossible for even the highest ground-based observatories to see, while limiting the cost of launching and maintaining an orbiting space-based telescope.

January 12, 2010

Minerals on Mars

Image courtesy NASA/JPL-Caltech/University of Arizona

January 11, 2010—It might look like a closeup shot of a seashell, but this recently released image is actually a sky-high view of Juventae Chasma in the Valles Marineris region of Mars.

Taken by NASA's Mars Reconnaissance Orbiter, the picture shows bright deposits of silica and sulfates under a darker mantle. These minerals suggest that cold, acidic water was at work on the Martian plateau during the Hesperian era, a period in ancient Mars's history marked by a shift to drier conditions.

January 12, 2010