A pair of bright spots on Ceres continues to baffle NASA scientists as the space agency’s Dawn spacecraft approaches being captured into orbit of the dwarf planet. Images taken 29,000 miles from the surface reveal the two bright spots.
“Ceres’ bright spot can now be seen to have a companion of lesser brightness, but apparently in the same basin. This may be pointing to a volcano-like origin of the spots, but we will have to wait for better resolution before we can make such geologic interpretations,” said Chris Russell, principal investigator for the Dawn mission, based at the University of California, Los Angeles.
“The brightest spot continues to be too small to resolve with our camera, but despite its size it is brighter than anything else on Ceres. This is truly unexpected and still a mystery to us,” added Andreas Nathues, lead investigator for the framing camera team at the Max Planck Institute for Solar System Research, Gottingen, Germany.
NASA scientists say that the Dawn spacecraft will begin entering the dwarf planet’s orbit on March 6. The agency says that they hope to get better views over the next 16 months to study its surface. Their goal is to “gain a deeper understanding of [Ceres’] origin and evolution.”
Ceres is a dwarf planet with a surface area of about 1.1 million square miles, or about 179 times smaller than Earth.
A 2006 debate in the scientific community regarding the definition of a planet nearly led to Ceres being classified as the fifth planet inside the asteroid belt and the twelfth in the solar system. Instead, scientists adopted a narrower definition that required a planet to “clear the neighborhood around its orbit” — or in other words, to dominate the space around its orbit. Ceres does not meet the criteria of a planet under this definition as it occupies the space with thousands of other asteroids. The same standards set in 2006 changed the status of Pluto from a planet to a dwarf planet.
The Dawn spacecraft previously visited the giant asteroid Vesta from 2011 to 2012, delivering over 30,000 images and providing other measurements to gain insight into its composition and geological history. Vesta is roughly half the size of Ceres with a surface area equivalent to Pakistan. Together, Ceres and Vesta are the two largest bodies in the asteroid belt between Mars and Jupiter.
NASA also captured the following two images: