Mercury is shrinking faster than we thought. What's going on inside of it?
New research indicates that Mercury is shrinking 10% to 30% faster than previously estimated, likely due to its internal composition. Scientists believe the planet's cooling core and metal content are driving this contraction, which was previously masked by cratering.
Why it matters
Understanding the rate of Mercury's contraction provides critical insights into the formation and internal thermal evolution of rocky planets in our solar system.
Solar System Mercury Mercury is shrinking faster than we thought. What's going on inside of it? News By Robert Lea Published 10 September 2026 "It made us think that there's a process obscuring shortening structures."
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Click for next article An illustration of a shrinking Mercury. (Image credit: Robert Lea (created with Canva)) Copy link Facebook X Whatsapp Reddit Pinterest Flipboard Email Share this article 0 Join the conversation Follow us Add us as a preferred source on Google Newsletter Subscribe to our newsletter Wrinkles on the surface of Mercury have revealed that the closest planet to the sun is shrinking faster than scientists thought.
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