Photo of a Nuclear Explosion Less than 1 Millisecond After Detonation Captured less than 1 millisecond after the detonation using a rapatronic camera, which is capable of exposure times as brief as 10 nanoseconds. The photograph was shot from roughly 7 miles away during tests in Nevada (1952). The fireball is roughly 20 meters in diameter, and three times hotter than the surface of the sun.
This photo of the fireball of the Greenhouse "George" shot was taken 30 milliseconds after the detonation. This test device was among the United States' first thermonuclear experiments. The yield was 225 kilotons (kt), a record held until the Ivy Mike test on November 1, 1952.