George Van Tassel’s Integratron

One of three sisters who co-own the dome, Nancy Karl, 48, walks by an alien art installation by high desert artist Johnette Napolitano. Karl and her sister Joanne have planted fruit trees and grapevines on the Integratron’s 10-acre site in San Bernardino County, where they live part time in customized vintage trailers.  (Irfan Khan / LAT)

Sisters Joanne Karl (left) and Nancy Karl (right) describe the therapeutic acoustic properties of the Integratron’s 38-foot high Douglas Fir dome. The structure is made entirely of wood and fastened by a 1.5-ton concrete ring at the building’s oculus.  (Irfan Khan / LAT)

Visitors to the dome, who can experience a 30-minute “sound bath” of tones produced by special quartz bowls, leave behind spiritual mementos on a makeshift altar. Keepsakes include an old ear trumpet, a Tibetan Buddhist painting, Native American feathers and a set of dentures.  (Irfan Khan / LAT)

Nancy Karl plays a set of pure quartz singing bowls in the Integratron with two rubber-tipped wooden sticks wrapped in suede. The bowls sound each note of the scale and reverberate through the domed space in specially designed “sound baths.”  (Irfan Khan / LAT)

Nancy Karl demonstrates a 1940s ear trumpet that was used to hear “voices from beyond,” she said. The device was donated by a late friend of George Van Tassel’s and longtime Landers resident who supported the Integratron and befriended the Karl sisters.  (Irfan Khan / LAT)

A Yoda Pez dispenser rests on the windowsill of the ad hoc altar inside the Integratron’s upper chamber. Artists, musicians, spiritualists and curious tourists visit the strange white dome, built over 18 years starting in 1957, plopped in the high desert.  (Irfan Khan / LAT)

Nancy Karl, co-owner of the Integratron, plays a small, handheld singing bowl. She quit her technology marketing job in 2001 to move to Landers with her sister and restore the 1960s-era dome.  (Irfan Khan / LAT)

The “Uncle Bob” figurine is a talisman bequeathed to the Integratron by a classical guitarist from Los Angeles who rents out the dome’s space to compose the movie themes he writes.  (Irfan Khan / LAT)

Visitors to the Integratron, a rejuvenating dome built -- but never completed -- by a former aircraft engineer, leave religious and spiritual souvenirs of their stop at the Landers, Calif. outpost.  (Irfan Khan / LAT)

Other spiritual mementos dropped at the dome’s makeshift shrine include recovery coins from Alcoholics Anonymous, and a garden of crystals. George Van Tassel was inspired to build the Integratron after a pre-dawn meeting with a visitor from Venus named Solgonda.  (Irfan Khan / LAT)

The Integratron’s designer and visionary, former aircraft engineer George Van Tassel, lived with his family in a hollowed-out chamber under Giant Rock, left. The seven-story, free-standing boulder, adjacent to the bare dirt landing strip that is Giant Rock Airport, sits about three miles north of Van Tassel’s unusual legacy, the Integratron.  (Irfan Khan / LAT)