Space & Astronomy

Mystery of the bright spots on Ceres solved

By T.K. Randall
December 12, 2015 ·  4 comments

The bright spots appear to be salt and water ice. Image Credit: NASA/JPL-Caltech 2015 has been a very fruitful year for space exploration and the visit by NASA's Dawn spacecraft to the dwarf planet Ceres, which lies in the asteroid belt between Mars and Jupiter, was no exception.

Even before the spacecraft had reached its target it sent back a series of tantalizing photographs showing strange bright areas within a crater on its surface - a mystery that would continue to deepen as the probe neared its destination and the phenomenon was revealed in more detail.

Now finally after months of analyzing the images and data returned by the mission, scientists believe that they have finally determined exactly what the bright spots are and how they came in to being.The answer lies just beneath the surface of Ceres' coating of rocks and rubble where there exists a planet-wide layer of ice and salt. When asteroids impact the planet, this layer is exposed and the ice begins to turn in to a gas - releasing vapor and lifting ice and dust particles in to the air.

When this 'haze' eventually fades away the ice is driven off and all that's left are deposits of salt.

"It's a bit like a comet, but you need to understand that Ceres is a partially differentiated body. So, it has a shell structure," said Andreas Nathues,who heads up Dawn's camera team.

"There is very likely an ice shell below the crust. And this is completely different from comets. Comets are primitive objects, having original material that is only very, very slightly changed."

Source: BBC News | Comments (4)

Tags: Ceres, Dawn