University of Hawaii researchers have found a rocky comet made of the same material that formed the inner solar system billions of years ago, providing information that could help pull back the curtain on the formation of the solar system.
The comet, dubbed C/2014 S3, was spotted by the University of Hawaii’s Prototype Telescope 1 at Haleakala on Maui in September 2014, according to a paper published Friday in the journal Science Advances. The lead author is Karen Meech of UH’s Institute for Astronomy.
The telescope is part of the UH Institute for Astronomy’s Panoramic Survey Telescope and Rapid Response System, or Pan-STARRS, which has a goal of discovering objects approaching Earth that might pose a danger to the planet.
Follow-up observations were made with the European Southern Observatory’s Very Large Telescope in Chile and the Canada- France-Hawaii Telescope on Mauna Kea, according to the paper.
The researchers determined the comet orbits the sun about every 860 years, suggesting that it has come from the Oort Cloud, a spherical cloud of rocks around the outer edge of the solar system.
Careful study of the light reflected by the comet led scientists to conclude that it is made of fresh inner solar system material that has been stored in the Oort Cloud for a long time. The comet is also not icy and doesn’t have the characteristic tail of comets approaching the sun, prompting scientists to name it the Manx comet after the tailless cat.
Essentially, the Manx comet is an asteroid that resides where comets do — not in the asteroid belt between Mars and Jupiter.
“We already knew of many asteroids, but they have all been baked by billions of years near the Sun,” Meech added in a statement. “This one is the first uncooked asteroid we have found: It has been preserved in the best freezer there is.”
Different models of the solar system’s formation make different predictions about the amount of inner solar system material in the Oort Cloud.
One model has the planets forming in a gas-rich disk and scattering inner solar system material outward to the Oort Cloud as the planets moved inward.
The discovery of the rocky comet could help scientists determine which of the several models of solar system formation is most accurate, based on the number of objects found.