A while back the Dawn spacecraft took some photographs of the surface of Ceres while it was first approaching, and there were these surprising, mysterious white dots that nobody could explain. For example, in Sky & Telescope's Bright Spots on Ceres Intrigue Scientists:
NASA's Dawn spacecraft is just a few days from arriving at its second and final objective, asteroid 1 Ceres, on March 6th. Robert Mase, who manages the mission at the Jet Propulsion Laboratory in California, says Dawn will be captured into orbit at 4:20 a.m. (12:20 Universal Time). That's the first critical step in what promises to be an intensive, 16-month-long investigation.
But images recently captured by the spacecraft's German-built camera already have mission scientists scratching their collective heads. Tucked inside a 57-mile-wide crater are two tiny spots far brighter than their surroundings. (emphasis added)
Unfortunately, after that school commitments started to pile up, and I was unable to continue following closely and watch the story unfold. Has anyone figured out what those white dots are? What are the current theories on it?
Figure caption:
NASA's Dawn spacecraft recorded this view of asteroid 1 Ceres on February 19th while still 29,000 miles (46,000 km) from its destination. Scientists were surprised to see the pair of bright spots inside a medium-size crater. NASA / JPL / UCLA / MPS / DLR / IDA
below: from https://dawn.jpl.nasa.gov/multimedia/images/image-detail.html?id=PIA21405