Physics

Calls to restart nuclear weapons tests stir dismay and debate among scientists

A U.S. return to underground detonations would have wide-ranging implications

The smoke plume from a nuclear test in Bikini Atoll along a beach front.

In 1946, the United States conducted this nuclear test at Bikini Atoll. Tests moved underground in the 1960s to limit nuclear fallout. After decades of hiatus, the United States may resume underground tests, some experts say.

Science History Images/Alamy Stock Photo

By Emily Conover

When the countdown hit zero on September 23, 1992, the desert surface puffed up into the air, as if a giant balloon had inflated it from below.