In the wee hours of Aug. 24, 1953, George Van Tassel, a 43-year-old former aviation engineer, was awakened by a man from outer space. Six years earlier, Van Tassel had moved with his family to Landers, Calif., a place of stark beauty and rainbow sunsets in the southeastern corner of the Mojave Desert, 40 desolate miles due north of Palm Springs. Van Tassel had the clean-cut look of a midcentury company man, and a résumé to match: He had worked for Lockheed and Douglas Aircraft, and for Howard Hughes’s aviation concern. But his spiritual leanings were esoteric. He settled in Landers because of its proximity to Giant Rock, an enormous seven-story-high desert boulder in whose shadow he would sit silently for hours at a stretch. He told friends that he went to Giant Rock to commune with the spirits of American Indians, who had regarded the boulder as sacred. But on that night in 1953, Van Tassel’s visitor was not a Native American. He was, Van Tassel claimed, a Venusian: the captain of a “scout ship” from Venus that had landed on the airstrip abutting Van Tassel’s property. The spaceman looked like a human, wore a gray one-piece bodysuit and spoke, Van Tassel told a television interviewer, “in the best English, equivalent to Ronald Colman’s.” He informed Van Tassel that his name was Solganda and that he was 700 years old. (He looked no older than 28, Van Tassel said.) Van Tassel was ushered onto the spacecraft where he was told that Earthlings’ reliance on metal building materials was interfering with radio frequencies and disrupting interplanetary “thought transfers.” Solganda also divulged a secret: a formula that Van Tassel could use to build a remarkable machine, a device that would generate electrostatic energy to suspend the laws of gravity, extend human life and facilitate high-speed time travel. Van Tassel died in 1978; Solganda hasn’t been heard from in decades, presumably having settled, at the ripe age of 750-something, into a comfortable Venusian retirement. But Giant Rock is still in Landers — a hulking mass that rises out of the desert like an immense beached whale. Three miles south of Giant Rock, across a scrubby expanse, you will find an even more extraordinary sight: a circular, dome-topped building, 38 feet tall and 55 feet in diameter, constructed by Van Tassel over the course of nearly two decades in accordance with the instructions of his extraterrestrial architectural patron. A sign above the gated entrance to the property proclaims the name that Van Tassel gave to his time machine: the Integratron. “It’s the most amazing structure I’ve ever seen,” says Joanne Karl, who bought the building 14 years ago with her sisters Nancy and Patty. In fact, the Integratron is a sort of time machine, or at least a time capsule. It is an immaculately preserved artifact of midcentury modernist design, and a totem of 1950s U.F.O.-ology culture — the mixture of Cold War paranoia and occult spirituality that drew true believers to remote reaches of the Desert Southwest in search of flying saucers and free-floating enlightenment. Under the ownership of the Karls, it has become a unique tourist destination: perhaps the oddest spot in a very odd corner of the world, a magnet for new generations of spiritual questers and for the just plain curious. “Nobody comes to the Integratron and just shrugs,” says Joanne. “You don’t leave and say, ‘Oh, that was nothing.’ ”

Photo Photo Every visitor to the Integratron is on some level a pilgrim: It’s not a place that you just happen by. To reach the building, you wend through a sun-strafed landscape of Joshua trees and bare-rock outcroppings on a series of progressively smaller roads. Finally you spot it: a bright white dome jutting out from the dust that can at first glance appear to be a mirage — a U.F.O. that has touched down on the Mojave moonscape. The building’s brilliant whitewashed facade is not merely decorative, it’s adhesive. The Integratron was constructed without nails, screws, flashing or weather stripping. “It’s just paint and caulk that keeps the weather out,” says Nancy. Inside the building, more engineering marvels await. You enter the Integratron through a set of double doors on its south side. A small stairway takes you from the ground floor, where there are exhibitions detailing the Integratron’s history, to the main attraction: the gloriously airy upper story. There, 16 rectangular windows offer 360-degree views of the desert, and the building’s wooden ribs, fashioned by shipbuilders, vault to the top of the dome. With the exception of a one-ton concrete ring that fixes those ribs in place, the whole thing — floor, walls, ceiling — is made of wood, old-growth Douglas fir from Washington State, which, if the lore is to be believed, Van Tassel was given as a gift by his old boss Howard Hughes. The wood lends a quaintly homey quality to the soaring space. It feels like the world’s most majestic clubhouse. But it’s not the way the Integratron looks that draws thousands to Landers each year. It’s how the place sounds. The Karl sisters tout the Integratron as “an acoustically perfect” space, a “resonant tabernacle” whose form and materials — its curvilinear dome and reverberating wood — act as natural amplifiers, a surround-sound stereo system in the shape of a building. For fees ranging from $20 to $80, visitors can experience a so-called sound bath, reclining on mats while the sisters strike and stroke quartz-crystal singing bowls, producing tones that ripple and swirl through the building’s main chamber. The result, the Integratron’s website promises, is “sonic healing”: “waves of peace, heightened awareness and relaxation of the mind and body.” It was a quest for sonic healing that brought the Karls to the Integratron in the first place. They visited Landers in the late 1980s on the advice of a friend, when the Integratron was in the hands of its second owners, Emile Canning and Diana Cushing. (Canning and Cushing purchased the property from George Van Tassel’s widow for $50,000.) The Karl sisters soon became part of a circle of Integratron regulars — traveling to Landers on weekends, sleeping in their rental cars and spending days beneath the dome in marathon sound-immersion sessions.

Photo “We experimented with every possible kind of sound,” Joanne remembers. “We played everything you could possibly play on a stereo: ZZ Top. Monks chanting. Om-ing kind of tapes. We had 20 hours of wild dolphin sounds from a marine biology professor. And then there were drums, you know — people would bring drums and we would drum for a whole bunch of hours. We weren’t musicians, but it would change us. We would play them until we were catatonic. I used to be known as the Governess of Catatonia.” When the building came up for sale in the year 2000, the Karl sisters pooled their resources and bought it. Patty remained at her home in Pennsylvania, while Joanne and Nancy relocated to the desert to run the operation. For both sisters, it was a radical shift in career and lifestyle. They were successful professionals who had raised families in tony coastal enclaves. Joanne had lived for years in Sag Harbor, N.Y., in the Hamptons, where she worked in cardiac research and development. Nancy, a marketing specialist, was a resident of Marin County in Northern California. “It just feels like a thing that had to happen,” Nancy says. “The longer you’re here, the more the desert works on you.” On an afternoon in early June, Nancy, 56, and Joanne, 60, could be found milling around the small compound that sits just beyond the fenced perimeter of the Integratron. When the Karls bought the Integratron, the building and environs had gone to seed — “It was Tumbleweed City,” Nancy says — but they have transformed it into an exceptionally pleasant place. Outside a low-slung office building, a little desert garden blooms: eucalyptus, pine, almond, pistachio, plum, apricot, olive and tamarisk trees, all planted by the Karls. The sisters preside over the Integratron with a mix of shaggy informality and military precision. They coordinate sound baths and other activities on walkie-talkies, answering to code names. (Joanne’s handle: “Lucid.” Nancy’s: “Rock It.”) When prodded, they will grudgingly discuss their business — it’s booming, they say, sound baths are booked solid — and supply names of the movie stars (Charlize Theron, Robert Downey Jr.) and musicians (Robert Plant, Josh Homme from Queens of the Stone Age) who’ve visited the Integratron. But the Karls don’t like being called “owners.” Their preferred term is “stewards” — they are, they say, custodians of the Integratron’s history and full-time probers of its mysteries. They caution a reporter not to depict them as “crazy New Age witches.” Yet their hippie streak is undeniable. You will not spend a long time with the Karls before talk turns to chakras, energy fields and the “powerful geomagnetic vortex” atop which the Integratron sits. But who can blame them? To spend even an hour at the Integratron is to find your mind opening to esoteric possibilities — to feel your doubts melting away beneath the desert sun, skepticism bending toward curiosity. You may not go as far as the thousands who traveled here decades ago, when Van Tassel hosted the annual Giant Rock Spacecraft Convention, a gathering of U.F.O. enthusiasts and alien “contactees.” You may not subscribe to Van Tassel’s belief that ancient Egyptians were capable of levitating “anything, including themselves,” that there are spaceship bases on the moon, that the Integratron is capable of rejuvenating your cells and reversing the aging process.

Photo But an Integratron sound bath will startle your ears, and, perhaps, awaken your imagination. The crystal singing bowls have a ventriloquial effect: Their tones seem not to emanate from the instruments themselves, but to hover and dart in midair, an effect that is enhanced by the Integratron’s awesome acoustics. Lying back beneath the wooden dome, it seems at moments that you’re not listening to sound so much as inhabiting it — that you’re on the inside of a musical instrument, in the hollowed belly of a massive cello. It is, aesthetically speaking, extraterrestrial: a transportative encounter with music, an experience of pure sound not quite of this earth. “Ninety percent of what goes on here is beyond the visible eye perspective,” Nancy says. “And that’s why so many people, when they come here, if you were to say to them, ‘Well, describe it,’ they’d say, ‘Just go.’ Because it’s experiential. You really kind of have to come and hang out.”