Scientists at the German Aerospace Center’s Institute of Space Research report that the planet Mercury has been shrinking for billions of years and may be contracting faster than previously estimated. This is according to a new paper published in Geophysical Research Letters and detailed by Futurism and other outlets. The study states the planet may have lost up to 14.5 miles of total diameter since its formation, a figure that is 10 to 30 percent more than earlier estimates. Researchers attribute the shrinkage to the planet running out of heat over time, a process described in an accompanying press release as being “like a balloon left out in the cold.”
Mercury is already the smallest planet in the solar system, at about one-third the size of Earth, according to NASA. The revised shrinkage rates suggest Mercury’s interior structure or thermal history may differ from prior models. The paper’s authors said the new rates better reflect previous physics-based predictions and align more closely with theoretical models of how the planet should behave as it cools.
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