Planet Mercury is Slowly Shrinking

in space on 2014-03-17 08:01 (#3G5)

According to a research published by Nature Geoscience, but not yet online, the planet "Mercury shrunk by more than 7 kilometers in radius over past 4 billion years". Using analysis of NASA's Messenger probe , researchers at the Carnegie Institution for Science say the planet lost seven kilometers (more than four miles) of elevation in some areas, over the course of four billion years. Scientists first suggested the phenomenon in the mid-1970s, when the Mariner 10 probe passed the planet in three flybys.

Re: Incredible (Score: 2, Informative)

by rocks@pipedot.org on 2014-03-17 19:45 (#MK)

"The innermost world has shrunk as it has cooled over time, its surface cracking and wrinkling in the process." from the BBC

The amount of cooling/shrinking depends on the composition of the planet and is being used to estimate the radius of its core.