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 If a country wants keep its nuclear bomb tests secret, it'll probably do it deep underground. But, even if you bury the bomb, some clues are reached the surface. So says the study in journal Geophysical Research Letters. Scientists analyzed¹ the radar² satellite data of spotting western China, where 3 nukes were ?? underground in the 90s. And they found that after the blast, the land above the test chainbers gradually swell³ the one inch higher in elevation⁴. Here's why. Shock waves from the explosion left the cracks in the rocks ?? surface. Years later, ?? of underground water still steemy from the blast, trickle⁵ up in enfoutrating those cracks, causing the rocks to expand and rise. Forensic⁶ evidence, they could be used to infer the bomb's explosive energy. International atomic energy agency won't be basting⁷ nuclear rabbles with this ?? time soon. It took four years for this bold in Chinese desert to appear. But since size make an analysis, the other tools for studying bomb blast can be foiled by a dead nation chainber. This trick gives nuclear detectives one more way to study blasts from the past.