Harold Agnew

Harold Melvin Agnew (March 28, 1921 – September 29, 2013) was an American physicist, best known for having flown as a scientific observer on the Hiroshima bombing mission and, later, as the third director of the Los Alamos National Laboratory.

Harold Melvin Agnew was born in Denver, Colorado on March 28, 1921, the only child of a pair of stonecutters.

He attended South Denver High School and entered the University of Denver, where he majored in chemistry.

He was a strong athlete who pitched for the university softball team that won a championship.

Agnew joined the Metallurgical Laboratory at the University of Chicago in 1942, and helped build Chicago Pile-1, the world's first nuclear reactor.

He left the University of Denver in January 1942, but had enough credits to graduate Phi Beta Kappa with his Bachelor of Arts degree in June, and he received a scholarship to Yale University.

After the Japanese bombing of Pearl Harbor brought the United States into the Pacific War, Agnew and his girlfriend Beverly, a fellow graduate of South Denver High School and the University of Denver, attempted to join the United States Army Air Corps together.

They were persuaded not to sign the enlistment papers.

Instead, Joyce C. Stearns, the head of the physics department at the University of Denver, persuaded Agnew to come with him to the University of Chicago, where Stearns became the deputy head of the Metallurgical Laboratory.

Although Agnew had enough credits to graduate, Beverly did not and had to remain behind.

They were married in Denver on May 2, 1942.

They then went to Chicago, where Beverly became a secretary to Richard L. Doan, then head of the Metallurgical Laboratory.

Agnew and Beverly had two children, a daughter Nancy, and a son, John.

At the Metallurgical Laboratory, Agnew worked with Enrico Fermi, Walter Zinn and Herbert L. Anderson.

There, he was involved in the construction of Chicago Pile-1.

Initially, Agnew worked with the instrumentation.

The Geiger counters were calibrated using a radon-beryllium source, and Agnew received too high a dose of radiation.

He was then put to work stacking the graphite bricks that were the reactor's neutron moderator.

He witnessed the first controlled nuclear chain reaction when the reactor went critical on December 2, 1942.

In 1943, he joined the Los Alamos Laboratory, where he worked with the Cockcroft–Walton generator.

After the war ended, he returned to the University of Chicago, where he completed his graduate work under Enrico Fermi.

Agnew and Beverly moved to the Los Alamos Laboratory in March 1943.

Agnew, Beverly and Bernard Waldman first went to the University of Illinois, where the men disassembled the Cockcroft–Walton generator and particle accelerator while Beverly catalogued all the parts.

The parts were shipped to New Mexico, where Agnew and Beverly met up with them, and rode the trucks hauling them to the Los Alamos Laboratory.

There, Beverly worked as a secretary, initially with Robert Oppenheimer and his secretary Priscilla Green.

She then became secretary to Robert Bacher, the head of Physics (P) Division, and later the Gadget (G) Division, for the rest of the war.

Agnew's job was to reassemble the accelerator, which was then used for experiments by John Manley's group.

When experimental work wound down, Agnew was transferred to Project Alberta, working as part of Luis W. Alvarez's group, whose role was to monitor the yield of nuclear explosions.

With Alvarez and Lawrence H. Johnston, Agnew had devised a method for measuring the yield of the nuclear blast by dropping pressure gauges on parachutes and telemetering the readings back to the plane.

In June 1945, he was issued an Army uniform and dog tags at Wendover Army Air Field, Utah, and was flown to Tinian in the Western Pacific in a C-54 of the 509th Composite Group.

Agnew's first task was to install his yield measurement instrumentation in the Boeing B-29 Superfortress aircraft The Great Artiste.

During the atomic bombing of Hiroshima, on August 6, 1945, Agnew, along with Alvarez and Johnston, flew as a scientific observer in The Great Artiste, piloted by Charles Sweeney, which tailed the Enola Gay as the instrumentation aircraft.

Agnew later recalled, "After we dropped our gauges I remember we made a sharp turn to the right so that we would not get caught in the blast – but we still got badly shaken up by it."

He brought along a movie camera and took the only existing movies of the Hiroshima event as seen from the air.

After the war ended, Agnew entered the University of Chicago, where he completed his graduate work under Fermi.

Agnew returned to Los Alamos in 1949, and worked on the Castle Bravo nuclear test at Bikini Atoll in 1954.

He also served as a Democratic New Mexico State Senator from 1955 to 1961, and was the Scientific Adviser to the NATO Supreme Allied Commander Europe (SACEUR) from 1961 to 1964.

He became head of the Weapon Nuclear Engineering Division in 1964.

He was director of the Los Alamos National Laboratory from 1970 to 1979, when he resigned to become President and Chief Executive Officer of General Atomics.

He died at his home in Solana Beach, California, on September 29, 2013.