by Brooks Hays
Baltimore (UPI) Mar 7, 2016
Astronomers have long struggled to explain Mercury's darkness, but new research suggests carbon is responsible for the planet's limited reflectivity.
Iron-rich minerals limit the amount of sunlight reflected by the moon, but Mercury is mostly without iron. Newly analyzed spectrometer data from NASA's Messenger probe instead reveals a high concentration of carbon on Mercury's surface.
When researchers at Johns Hopkins University and the Carnegie Institution for Science compared a map of carbon-rich deposits with a map of Mercury's reflectivity, they found a strong correlation between carbon and darkness.
"We used Messenger's Neutron Spectrometer to spatially resolve the distribution of carbon and found that it is correlated with the darkest material on Mercury, and this material most likely originated deep in the crust," Larry Nittler, Carnegie scientist and deputy principal investigator of the Messenger mission, said in a news release. "Moreover, we used both neutrons and X-rays to confirm that the dark material is not enriched in iron, in contrast to the Moon where iron-rich minerals darken the surface."
Models suggest that when Mercury was young it was so hot that the entire surface was one big ocean of magma. As the molten rock cooled, most minerals sank to the bottom. Graphite, being more buoyant, was left to solidify at the top, forming Mercury's first crust.
"The finding of abundant carbon on the surface suggests that we may be seeing remnants of Mercury's original ancient crust mixed into the volcanic rocks and impact ejecta that form the surface we see today," Nittler explained.
The new research was published this week in the journal Nature Geoscience.
News Flash at Mercury
Mars News and Information at MarsDaily.com
Lunar Dreams and more
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2016 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.|