Her book, "Area 51: An Uncensored History of America's Top Secret Military Base," is about the secretive Nevada base called Area 51. One chapter offers the new Roswell theory, citing an anonymous source who says Joseph Stalin recruited Mengele and sent the craft into U.S. air space in 1947 to spark public hysteria.
Like past theories, Jacobsen writes that the U.S. government was involved in a cover-up of the UFO report, which has spawned space alien legend and turned this southern New Mexico town into a tourist attraction.
IN PICTURES: UFOs
Bill Lyne, who self-published a book called "Space Aliens from the Pentagon" in 1993, agrees that the Roswell incident was faked, but he thinks the hoax was perpetrated by the U.S. government — not the Russians.
"They're just saying what I've been saying all along, that it was a hoax," he told the Santa Fe New Mexican. "But that Mengele stuff is a bunch of hogwash because Mengele was recruited by the CIA (rather than the Russians), and he was actually brought to Albuquerque."
Clifford Clift of the Mutual UFO Network, or MUFON, in Greeley, Colo., said he has not seen Jacobsen's book but has read other articles that suggest the Roswell incident involved German technology.
"After researching the claim, I found little truth in this theory," he said. "It is a stretch. One of my concerns is if they wanted to create panic, why in New Mexico and not New York where there are more people to panic? I would suggest it is another conspiracy theory and, heavens, MUFON knows about conspiracy theories. They do sell books."
Jacobsen, a contributing editor the Los Angeles Times magazine, told NPR that said she knows people will be skeptical.
"But I absolutely believe the veracity of my source, and I believe it was important that I put his information out there because it is the tip of a very big iceberg," Jacobsen said.
Julie Schuster, executive director of the International UFO Museum and Research Center in Roswell, told the Albuquerque Journal she hasn't read the book. But any new theories fuel public interest, and that's terrific, she said.
"Every time something new comes out, it piques somebody's curiosity somewhere, and they come to Roswell, and they come to the museum," Schuster said.