But here at the American Atheist headquarters, the world's most vocal and determined atheist has been missing for more than a year. Her continued silence, after 30 years of trumpeting her opinions about everything from prayer in the schools to the imprint of "In God We Trust" on the dollar bill, is the surest sign that Madalyn Murray O'Hair may never be coming back.

"It really doesn't do much good to speculate, because we don't really know what happened. Maybe this will become atheism's first mystery," said Ron Barrier, the national spokesman. "Who knows? Maybe she was taken bodily into heaven."

To officials of the country's largest atheist group, founded by O'Hair in 1965 and until last year the cornerstone of her life, the time has come to move on without their founder and longtime leader. "We don't have time to talk about something for which there is no new news," said Ellen Johnson, 40, a New Jersey homemaker who has succeeded O'Hair as president of the 40,000-member group.

Johnson and Barrier already have taken over the atheist cable television program, seen in 35 markets, that O'Hair hosted for many years. Their headquarters is again churning out atheist tracts that explain their positions against school prayer, and the Republican-propelled religious freedom amendment that, they believe, seeks to put the word, "God" into the Constitution. And they have settled down to concentrate on what matters most to them – defending their faith in a government without God.

But the disappearance of O'Hair, 77, along with her younger son, Jon Garth Murray, 42, and granddaughter, Robin Murray O'Hair, 31, continues to be a source of rumor, speculation and comedy. Even television's "Saturday Night Live" has weighed in, noting that O'Hair was missing and that her family had requested "everyone not to pray."

The mystery began last August, when the family, who worked together at the Austin headquarters, departed for a two-week vacation. When O'Hair did not return as scheduled, and even missed a chance to picket the pope in New York, local news reports emerged speculating that she was ailing and perhaps already dead. She had made no secret of her disdain for Christian deathbed scenes, and had often remarked that she did not want "those Christers," as she called them, praying over her soul.

Early on, one of her board members publicly remarked that O'Hair, who has diabetes, had seemed more tired than usual in the weeks leading up to her departure. But no one seems prepared to say that she is dead, only that she may have finally grown tired of public life. Barrier also dismissed the more outrageous rumors that followed her disappearance, especially the one suggesting she had fled to Tahiti with $100 million in American Atheist funds.

"There was no money missing. Everything is accounted for, everything is intact," he said. "We are operating under the assumption, and atheists do not like to assume, that they are not coming back. My deepest thoughts are, if they have experienced burnout and frustration, maybe this is the best thing for them, to go and relax. They have dedicated 30 years to this cause."

O'Hair's reputation as America's preeminent atheist was born with her 1962 landmark anti-school prayer case before the U.S. Supreme Court, a companion to the case that led to the banning of prayer in the public schools. Then a lawyer living in Baltimore, O'Hair grew incensed when her elder son, William J. Murray, returned from junior high school classes to report he was forced to participate in daily prayers.

In a dramatic twist, Murray, now 50, who is Robin's father, later renounced his mother's position and went on to lead the Washington, D.C.-based Citizens to Restore Voluntary School Prayer. The Washington Post attempted several times recently to reach Murray by telephone, but he has made it clear in the past that he is not interested in answering questions about his mother – or the daughter from whom he has long been estranged.

O'Hair, with her stern, sometimes scathing manner and the air of having more important things to do than bother with her clothing or her cropped white hair, was certainly a powerful symbol of the atheist movement, and seemed to enjoy being reviled for her opinions. She often called herself, "the most hated woman in America." But Barrier thinks she occupies a loftier place in history.

"I would like to see Madalyn go down in history as a woman who finally solidified the separation of government and religion in the United States," he said, "as a woman who solidified the dreams of Thomas Jefferson and James Madison of having complete freedom of religion in this country – meaning, of course, that whether or not one wanted to participate in a religion, and which religion was a decision by the individual, without any influence by the government."

But in a country that views itself as "one nation under God," that viewpoint also makes the group an easy target, Barrier said.

"The biggest misconception is that we're evil, we're immoral," he said. "One of the beautiful ones is that we're devil worshipers, which I find odd, because Satan is a Christian idea – good or bad, he's just another god. One of the biggest misconceptions we have had to try and disassociate ourselves with is, of course, that we're all Cold War communists. I'm no communist. I consider myself quite conservative – I'm even for instituting a peacetime draft. Does that sound like a communist?"

Barrier and other atheists recently found a new cause for alarm when Gordon B. Hinckley, leader of the Mormon church, told the national convention of the American Legion, "as you once knew so well, there are no atheists in foxholes," adding, atheism is a threat to American ideals and must be the new battlefield.

Orin "Spike" Tyson, a decorated veteran from Austin who is national commander of the American Atheist Veterans, shot back that Hinckley was "never in MY foxhole or in any of the other tens of thousands of atheist foxholes in Vietnam."

And, as they marshal forces for the post-O'Hair era, Barrier said the group also plans to work toward a special tribute to their departed leader, one likely to be just as controversial as any they have undertaken:

"I hope we can help Madalyn fulfill her dream, of having an American president, who, at his inaugural celebration, puts his hand on a copy of the Constitution rather than the Bible."