Space Photos This Week: Eclipse, Hubble Stunner, More

Easter Island Eclipse

Photograph by Juan Carlos Casado, TWAN

The moon briefly blots out the sun during a total solar eclipse seen from the Chilean territory of Easter Island (Isla de Pascua) on Sunday.

During a total solar eclipse, the moon passes completely between Earth and the sun, casting a circular shadow over the planet. On the ground, viewers in the full shadow's path—aka the path of totality—see the moon cover the sun's disk for several minutes. Only the sun's faint upper atmosphere, or corona, remains visible.

The full effect of Sunday's total solar eclipse was visible to just a few people along a narrow, 155-mile-wide (250-kilometer-wide) band of the Pacific Ocean. Starting north of New Zealand, the path of the moon's shadow swept over a few remote islands and ended over the southernmost tip of South America.

(See more pictures of Sunday's total solar eclipse.)

Published July 14, 2010

Wave Action

Image courtesy NASA

As the Barren Island Volcano (lower left) puffs steam, two types of waves zigzag across the Indian Ocean in a March 6, 2007, satellite image captured by the Advanced Land Imager (ALI) on the Earth Observing 1 satellite. Taken near the Andaman Islands (see map), the image was released by NASA on July 10.

Tiny wrinkles running horizontally across the ocean are surface waves, which ride on the top of the ocean currents. (Visit National Geographic's oceans hub.)

The long, dark, diagonal lines (right) are broad stripes of rough water, which reflect less light than smoother seas. These stripes are surface effects of internal waves, which move through the lowest layers of ocean water, never directly swelling the surface, according to Earth Observatory.

Published July 14, 2010

NASA Plays With Fire, Ice

Photograph courtesy NASA

Can NASA's next-generation solid-fuel booster rocket hum when cold? The answer may be revealed by September tests of developmental motor 2 (DM-2)—pictured at the Promontory, Utah, testing facility of contractor ATK Space Systems in an undated photo released July 6.

Before ignition, DM-2's motors will be cooled to 40 degrees Fahrenheit (4 degrees Celsius) to make sure the rocket performs well in cold weather.

Hot or cool, the future boosters are similar to those used by the space shuttle. But the new boosters  boast upgrades such as improved insulation to strengthen safety, performance, and reliability for future NASA launch vehicles—though that future is very much up in the air.

The new motors were designed for the Constellation moon-landing program, which is slated for cancellation under U.S. President Barack Obama's new plan for NASA, formally announced April 16. (Also see "Obama Scrubs NASA's Manned Moon Missions.")

Published July 14, 2010

Mars's Frosty Pole

Image courtesy NASA

A variety of surface textures are seen in a March 6, 2007, picture of Mars's south pole released July 7.

NASA's HiRISE camera snapped the picture during Mars's southern spring, when the surface is covered by carbon dioxide frost. The frost highlights the region's long troughs (right) as well as round pits and irregular mesas (left of center).

Such landforms are common in the south polar residual ice cap, which previous Mars Global Surveyor images have shown is eroding rapidly in places.

(Related: "Mars Pole Holds Enough Ice to Flood Planet, Radar Study Shows.")

Published July 14, 2010

Moon Rabbit Hole

Image courtesy NASA

New Lunar Reconnaissance Orbiter (LRO) images reveal sharper views of a "lunar rabbit hole" in the moon's Marius Hills, according to the NASA website.

"They could be entrances to a geologic wonderland," Mark Robinson of Arizona State University, principal investigator for the LRO camera, said on the website. "We believe the giant holes are skylights that formed when the ceilings of underground lava tubes collapsed."

Japan's Kaguya spacecraft first photographed the enormous caverns in 2009. (Take a moon myths and mysteries quiz.)

Published July 14, 2010

Big Disk

Image courtesy L. Calçada, ESO

A hot, dusty disk circles a young star in an artist's impression—a scene that may be as common for massive stars as for low-mass ones, according to a study in this week's issue of the journal Nature.

Scientists have long suspected that radiation pressure from nascent massive stars would keep the material from such disks from falling into—and helping to build—the bodies, as happens with low-mass stars.

But data from several telescopes has helped uncover hot material suggestive of such an accretion disk around a star about 20 times as massive as our sun.

Published July 14, 2010