At 5AM on a June morning in 1974, seismologist Lynn Sykes awoke to a phone call from the Department of Defense. The voice on the other end of the line asked Sykes to be ready to leave for Moscow that evening. The DoD needed his help to negotiate a treaty that would cap the size of the US and Russia’s underground nuclear explosions.

Sykes, now a professor emeritus at Columbia University’s Lamont-Doherty Earth Observatory, was invited because of his unusual expertise. Sure, he was an expert on earthquakes. But he was also an expert on underground nuclear explosions, which — like earthquakes — can send vibrations ringing through the Earth. So the same devices that monitor and measure quakes can do double duty as secret nuclear test sensors.

In his new book, Silencing the Bomb: One Scientist’s Quest to Halt Nuclear Testing, Sykes chronicles his efforts to end explosive nuclear testing. When Sykes visited Russia in 1974, nuclear testing in the atmosphere, underwater, and space had already been banned by the Limited Test Ban Treaty signed in 1963 — the result of public pushback against the perils of radioactive fallout.

But there was an ongoing debate about whether it was possible to tell the size of an underground nuclear explosion from the seismic wiggles picked up by monitoring stations. If there were no sure way to check if someone was cheating on the deal, then neither the US nor Russia wanted to stop underground tests altogether. That’s why Sykes was in Russia: to confirm that detecting underground tests was scientifically possible, and to help negotiate a treaty that would limit underground nuclear tests to 150 kilotons or less.

The negotiations were a success, and President Richard Nixon and Soviet premier Leonid Brezhnev signed the treaty about a month later. But the quest for a complete ban on nuclear testing continues. The Comprehensive Test Ban Treaty, which would ban all nuclear tests of all sizes, was finalized in 1996. But the US, China, Iran, and North Korea still need to ratify it in order for the treaty to enter into force.

In his new book, Sykes reflects on his 50-year career working toward a test ban that is still out of reach. But, he says, he sees the glass as nearly full, since no one except North Korea has exploded a nuke since 1998: “I consider that a big accomplishment,” Sykes tells The Verge. “I’m very sad that we didn’t have a full test ban way back then. But I did as much I could, I believe, to try and open up this problem.”  ………. https://www.theverge.com/2018/3/20/17143702/nuclear-testing-underground-explosions-lynn-sykes-book-silencing-the-bomb