A NASA spacecraft studying the dwarf planet Ceres has snapped dramatic images of the tiny world's surface, including a tall, cone-shaped mountain that has attracted much interest from scientists and the public alike.
When first seen in images taken by the Dawn spacecraft months ago, the 21,120-foot-tall mountain was dubbed a "pyramid," which sent conspiracy theorists in paroxysms of delight.
"Too regular to be natural," went their refrain.
Completely natural, came the scientists' response, but no less interesting for all that.
In new images, taken from just 915 miles above Ceres on Aug. 19, the "lonely mountain" — so tagged because it's not a part of any visible mountain range — turns out to be not a pyramid but rather quite conical.
The mountain is covered with bright streaks of unknown origin, similar to the dwarf planet's mysterious white spots, which might be ice or salt but that continue to baffle scientists.
The borders of the base of the mountain are very sharply defined, with almost no accumulated debris at the base of the brightly streaked slope, NASA said in a statement.
The new images of the largest object in the solar system's asteroid belt also show round impact features, craters and ridges.
They were obtained after the Dawn probe was moved to a new, closer orbit around Ceres.
"Dawn is performing flawlessly in this new orbit as it conducts its ambitious exploration," says Marc Rayman, Dawn mission director at the space agency's Jet Propulsion Laboratory in Pasadena, California. "The spacecraft's view is now three times as sharp as in its previous mapping orbit, revealing exciting new details of this intriguing dwarf planet."
The spacecraft needs 14 complete orbits around Ceres to snap images of its complete surface, NASA scientists point out, and in the next two months, it will capture six such complete views.
Even better images are to come, they explain, as they plan to send the spacecraft into an even closer orbit just 230 miles above the surface beginning in late October.
Dawn, launched in September 2006, is the first spacecraft to orbit two distinct solar system objects, circling the protoplanet Vesta for 14 months from 2011 to 2012 and arriving at Ceres in March 2015.
In addition to its high-resolution cameras, the $466 million spacecraft carries a visible and infrared mapping spectrometer to gather data that should give scientists clues to the minerals found on Ceres' surface.
