Ceres, the dwarf planet whose mysterious bright spots have held the public's attention, is revealing some of its secrets in the most recent images from NASA's Dawn spacecraft.
The space agency has released dramatic new images, captured as the Dawn probe made its closest orbit above the surface of Ceres, passing over it as just 240 miles away.
Taken during four days in December, the images highlight the Kupalo Crater, one of the tiny world's youngest.
Bright material exposed on the crater's rim could be salt, and could be related to the "bright spots" seen in earlier images of Ceres, which researchers suspect are large salt deposits.
"This crater and its recently-formed deposits will be a prime target of study for the team as Dawn continues to explore Ceres in its final mapping phase," says mission science team member Paul Schenk at the Lunar and Planetary Institute in Houston.
Another crater featured in the new images, Dantu Crater, shows fractures on its 78-mile-wide floor, similar to what are seen on our moon in the large young crater known as Tycho, researchers noted.
The cracking may be the result of cooling of materials melted by the impact, or the crater floor may have experienced uplifting after the forming of the crater, they suggest.
The Dawn spacecraft launched in 2007, headed to two solar system targets: Vesta and Ceres, to two larger objects orbiting in the asteroid belt that lie between Mars and Jupiter.
The probe arrived at Vesta in July 2011 and spent 17 months studying that tiny world before heading off to Ceres, arriving in orbit there in March 2015.
While Ceres, with a diameter of around 587 miles, is considered a dwarf planet, scientists classify the slightly smaller 326-mile-wide Vesta as an asteroid.
One of the goals of the Dawn mission was to contrast and compare the two bodies to gain an understanding of how they may have formed, NASA said in a statement.
To that end, other instruments on the spacecraft have been busy analyzing the various wavelengths of light reflecting off of Ceres, which can help identify minerals on its surface.
"When we set sail for Ceres upon completing our Vesta exploration, we expected to be surprised by what we found on our next stop," says mission principle investigator Chris Russell.
The dwarf planet did not disappoint, he says.
"Everywhere we look in these new low-altitude observations, we see amazing landforms that speak to the unique character of this most amazing world," says Russell, based at UCLA.
