The Manhattan Project

In partnership with the National Museum of Nuclear Science & HistoryNational Museum of Nuclear Science & History

Little Boy

Masao Tomonaga

Masao Tomonaga is the honorary director of the Japanese Red Cross Nagasaki Atomic Bomb Hospital and a hibakusha, an atomic bomb survivor. He studied internal medicine and hematology at the Nagasaki University Medical School. Currently, he runs a retirement home for older hibakusha. In this interview, Dr. Tomonaga discusses his experience surviving the bombing of Nagasaki. He outlines the immediate physical impacts the bomb had on people’s bodies, the long-term physical impacts, such as cancer, and the psychological harm.

John Coster-Mullen's Interview

Cindy Kelly: I’m Cindy Kelly. This is January 30th, 2017. We’re in Washington, D.C., and I’m with John Coster-Mullen. I want to start by asking him to say his name and spell it, please.

John Coster-Mullen: John Coster-Mullen, J-O-H-N C-O-S-T-E-R-M-U-L-L-E-N.

Kelly: Great. Some have called you “Atomic John.”

Coster-Mullen: Yes. 

Clay Kemper Perkins' Interview

Cindy Kelly: Today is February 3rd, 2017. I am Cindy Kelly, Atomic Heritage Foundation. I am in Albuquerque, New Mexico, with Clay K. Perkins. I would like him to first say his full name and spell it.

Clay Perkins: It’s Clay, middle initial K for Kemper, last name Perkins. C-L-A-Y K P-E-R-K-I-N-S.

Kelly: Tell us about who you are. Where are you from? When were you born, how you got interested in science?

Robert Furman's Interview

Robert Furman: Robert Furman. F-U-R-M-A-N. I was an assistant to General Groves in the Manhattan District, in his Twenty-First Street offices here in Northwest. And I joined him in late autumn of ‘43 and left him right after the war—right after the end of the war.

Cindy Kelly: Can we—just to—no one’s going to hear what I say, so. And don’t feel that I’m interrupting you because the beauty of editing is we can cut and paste things.

Furman: Sure.

Gun Site

The Gun Site (TA-8-1) was where Manhattan Project scientists and engineers developed and tested the gun-type weapon design. The design for the “Little Boy” bomb dropped on Hiroshima on August 6, 1945, was developed here.

The gun design was straightforward. Basically, a “bullet” of nuclear material was fired at very high speed into a second nuclear mass, creating a critical mass. This released enormous energy with an immense explosion. Scientists were confident the design would work and the gun-type bomb was not tested before it was used against Japan.

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