# Mercury is still shrinking as its massive core cools and cracks its crust 2026-08-10T08:49:09+00:00 | Health & Science | Indian Opinion Desk Corroboration: 1 independent outlet Mercury is still contracting, and new images from NASA's MESSENGER mission show that its cooling metallic core, which makes up nearly 85% of the planet's radius, continues to crack its thin crust. A study in Nature Geoscience catalogued 190 young grabens, or dropped strips of ground, many around 300 million years old or younger, clustered near the Caloris basin. The planet's core measures 2,074 km across, while the outer shell is only 400 km thick. NASA reports that earlier surveys underestimated Mercury's shrinkage by up to seven times. The European Space Agency's BepiColombo mission, set to enter orbit, should provide sharper images of these tectonic features. ## Coverage - timesofindia.indiatimes.com Tags: BepiColombo, Mercury, MESSENGER, NASA, planetary geology, space Canonical: https://indianopinion.org/mercury-is-still-shrinking-as-its-massive-core-cools-and-cracks-its-crust/ License: Summary and commentary (c) Indian Opinion, reusable with attribution. Facts belong to the linked sources. Cite: https://indianopinion.org/mercury-is-still-shrinking-as-its-massive-core-cools-and-cracks-its-crust/#story-in-brief Review state: restored archive article, accurate at time of publication, not offered to search indexes.