As the world commemorates the 60th anniversary of the bombings of Hiroshima and Nagasaki, a new book tells the story of the New Mexico desert laboratory where the first atomic bomb was made: Jennet Conant's 109 East Palace: Robert Oppenheimer and the Secret City of Los Alamos (Simon and Schuster). Ms. Conant's earlier bestseller, Tuxedo Park, described a World War II-era radar laboratory. Her second book continues the story of some of the same scientists, and draws on personal experience as well. Her grandfather, Harvard University President James B. Conant, was the administrator of the super-secret "Manhattan Project" that developed the atomic bomb.

Jennet Conant describes the controversy over the atomic bomb as the reigning debate of her childhood. Her parents were outraged by the allied bombings of Hiroshima and Nagasaki in August, 1945, and blamed her grandfather for his role in launching the nuclear age. Her grandfather and other Manhattan Project scientists suffered from deep remorse, even though they joined the project with what the author calls "the best of intentions."

"The idea really was that Germany was on the way to getting its own bomb," Ms. Conant says, "that it was ahead of us. The Manhattan Project was formed with a great number of Jewish and refugee scientists who had families in concentration camps and in occupied parts of Europe. So there was no moral ambiguity. There was the exact opposite, a tremendous sense of coming together to get this weapon built as quickly as possible to save Western civilization. It always seemed to me it had been a cruel trick of history that it wound up being used against the Japanese, dropped on cities so that hundreds of thousands of civilians were killed, and that these men bore this terrible weight of responsibility, when they really had started out doing very honorable service for their country."

Much of 109 East Palace is told from the perspective of a woman named Dorothy McKibben, who acted as the "gatekeeper" for Los Alamos. "I had grown up with this story always told as one of the most compelling episodes in history," Jennet Conant explains, "and I wanted to tell it the way the scientists had told it to me, their experience as very young men, 24, 25 years old, leaving their homes and going off into the desert. So I found the wartime memoir that had never been published of Dorothy McKibben. She was a young widow living in Santa Fe (New Mexico) in 1943, raising a little boy, when Robert Oppenheimer, the very charismatic, handsome physicist who was appointed head of the bomb laboratory, swept into town and hired her to be his assistant."

Jennet Conant says Robert Oppenheimer came to Santa Fe under an assumed name, and Dorothy Mckibbben had no idea what she would be doing. "But she started the next day in a tiny office at 109 East Palace," says the author, "which would become the front office for this classified laboratory on a mountain 35 miles out of town. And for 27 months she would lead a double life."

During those months, Dorothy McKibben would greet and often befriend some of the great scientific minds of the 20th century -- from promising young graduate students like Richard Feynman to illustrious nuclear pioneers like Enrico Fermi. Many of those cosmopolitan physicists were shocked by their first sight of the heavily guarded lab town, established on the site of a former boys school, enclosed by barbed wire and surrounded by barren New Mexico desert.

But Robert Oppenheimer eventually forged a community out of the more than 5,000 scientists, their families, support staff and military troops. "They organized little community theaters," Jennet Conant says. "They organized choral groups, church services, finally schools. It was like a pioneer camp. Physicists who'd never been on horseback learned to ride. There was also a very predictable outcome from limited power at night, and that was a baby boom. The first year at Los Alamos, 80 babies were born. By the second year 10 babies were being born a month. The army was obsessed with secrecy, and with no one knowing what Los Alamos was up to, the most common wartime rumor was that it was a home for pregnant army wives."

But even their wives knew little about what the scientists were racing to accomplish at Los Alamos. "We started this bomb project far behind the Germans," says Jennet Conant. "We caught up. We surpassed them. They never got even close to achieving a sustained fission reaction, a sustained chain reaction. And then actually building two different designs for the weapon -- one was a uranium gun bomb, one was an implosion bomb -- that really was, from a scientific point of view, an incredible achievement."

Jennet Conant's book draws on the personal stories and unpublished papers of her grandfather and other Los Alamos scientists, a number of whom were family friends. She even had eyewitness accounts of the Trinity test, the first explosion of the bomb in the New Mexico desert on July 16, 1945. "My grandfather kept a very meticulous diary of events," says the author. "He said that as minutes passed, and they saw that now-famous mushroom cloud go billowing up, and they realized that they had lived, and that this explosion was far greater than any explosion ever created by man before, their first reaction was awe, but then exhilaration because they'd done it. Twenty seven months in the desert of working around the clock and they had managed to pull it off. And then it just began to dawn on him that it was a weapon, not a mathematical calculation."

One of the Los Alamos physicists, Edward Teller, went on to become known as the "father of the hydrogen bomb," an even more powerful weapon of destruction. Robert Oppenheimer and the author's grandfather, James Conant, opposed the project. Mr. Oppenheimer was eventually stripped of his security clearance because of his opposition, and because of communist ties dating back to his youth. Edward Teller testified against him. Jennet Conant says the episode left a lasting rift in the scientific community-another controversial chapter in a story of brilliant science and human tragedy.