Mercury’s shrinkage since its formation has been a subject of debate among researchers. New research aims to provide more accurate estimates by employing an alternative method for analyzing fault data. A study published in AGU Advances found that the planet’s radius may have shrunk by 2.7 to 5.6 kilometers as it cooled.
The new approach, developed by Loveless and Klimczak, focuses on the largest fault in each dataset and scales its effects to estimate total shrinkage. This method bypasses the reliance on variable numbers of faults included in prior estimates.
Using three different datasets containing 5,934, 653, and 100 faults, researchers found that their method yielded consistent results: an estimated contraction of about 2-3.5 kilometers. When combined with previous estimates of shrinkage caused by other cooling-induced processes, the total range becomes 2.7 to 5.6 kilometers.
The study sheds light on Mercury’s long-term thermal history and may also aid in understanding the tectonics of other planetary bodies like Mars, which feature faults.
Source: https://www.space.com/astronomy/mercury/how-much-has-mercury-shrunk