NASA’s Dawn spacecraft got its first sight of mysterious bright spots on the dwarf planet Ceres on final approach early this year, and scientists released the nearest view of the features.
The brightest points in the crater are clustered within a 55-mile (90-kilometer) across. The markings consist of several small spots with different sizes and frames.
Dawn arrived there June 3 and started collecting science data from its new operating post June 5 after a four-week descent from a higher orbit. The latest image from Dawn was one of the first photos the spacecraft took from its new orbit 2,700 miles from Ceres (4,400 kms).
Scientists revealed that Ceres shows evidence of surface activity, including flows, landslides and collapsed structures, however, the body shiny markings have gotten the most attention so far.
“The bright spots in this configuration make Ceres unique from anything we’ve seen before in the solar system,” said by Dawn’s principal investigator, Christopher Russell. “The science team is working to understand their source.”
Researchers forecasted that Dawn would encounter an icy world when the probe arrived at Ceres, hence ice is the natural assumption for the make-up of the bright spots.
“Reflection from ice is the leading candidate in my mind, but the team continues to consider alternate possibilities, such as salt,” Russell said in a statement. “With closer views from the new orbit and multiple view angles, we soon will be better able to determine the nature of this enigmatic phenomenon.”
In a press release, NASA said that measurements from Dawn’s infrared mapping spectrometer will help scientists determine the source of the spots.
Scientists have discovered Ceres stretches 599 miles across (963 kilometers) across at its equator. It is the most massive object in the asteroid belt between the orbits of Mars and Jupiter.
Ceres is the second previously-unexplored body Dawn has visited. It launched in 2007, orbited the giant asteroid Vesta in 2011 and 2012, and then started the expedition to Ceres, and it reached in March.
Dawn will fly eight times in its current orbit around Ceres until June 28, when it will begin to spiral closer to the draft planet, heading for a 900-mile (1,450-kilometer) orbit in early August. Dawn is programmed to be closest to Ceres at an altitude of 232 miles by the end of the year.