Happy 55th!

To Ivy-Mike and the thermonuclear age.

The fireball was over 3 miles (5 km) wide, and the mushroom cloud rose to an altitude of 57,000 feet (17.0 km) in less than 90 seconds. One minute later it had reached 108,000 feet (33.0 km), before stabilizing at 120,000 feet (37.0 km) with the top eventually spreading out to a diameter of 100 miles (161 km) with a stem 20 miles (32 km) wide.

The blast created a crater 6,240 feet (1.9 km) in diameter and 164 feet (50 m) deep where Elugelab had once been; the blast and water waves from the explosion (some waves up to twenty feet high) stripped the test islands clean of vegetation, as observed by a helicopter survey within 60 minutes after the test, by which time the mushroom cloud and steam had been blown away. Irradiated coral debris fell upon ships stationed 30 miles (48 km) from the blast, and the immediate area around the atoll was heavily contaminated for some time.

Before:
After: