Moon shrinking, say scientists Astronomers have declared that the moon is shrinking after spotting wrinkles all over the lunar surface. The tell-tale contraction marks were discovered by U.S. scientists who examined thousands of photographs of the moon’s surface taken by a Nasa orbiter. Some of the wrinkles are several miles long and rise tens of metres above the dusty terrain. Researchers believe they arise from the moon decreasing in size by around 200 metres across its diameter. The moon’s mean diameter is generally calculated to be 3,474 kms. The prospect of a shrinking moon is not new to planetary experts. When the moon formed it had a hot core, much like that of the Earth, which caused it first to expand and then contract as it cooled down. The latest findings suggest the moon could still be cooling, a process that causes the surface to compress and form the wrinkle-like features, known as lobate scarps. A team led by Thomas Watters at the Smithsonian Institution in Washi...