The CUFOS group employed a psychologist and social worker to interview abductees and their family members and tried to compare them with the normal population. Their conclusion?

"Most people who believe they were taken aboard a UFO are normal people. A small percentage aren't normal, but they're not crazy--they might have certain tendencies like borderline personality," said Rodeghier, who also admits that most cases can be explained by sleep paralysis, disguised memories of sexual trauma and other explanations.

"I can't just say people are being abducted, some people will, but I won't. There's not enough evidence," Rodeghier said. "I can say that I can't explain some of this stuff ... people do have missing time that's not accounted for. It's strange."

Obtaining evidence of UFOs is still a major goal for CUFOS, which is spearheading a project to get high-tech cameras to monitor certain parts of the sky for 24 hours a day. The cameras would gather video, and also track weather conditions and the electromagnetic field. The key is raising the money to buy the cameras and finding the ideal places to put them.

"It's tough because you can't predict where UFOs will be seen," Rodeghier said.

Indeed, UFO spotting has become an increasingly rare thing over the last decade, according to Rodeghier. In decades past, people used to see lots of metallic saucers and various creatures--from little grey aliens and reptilian beings to "Nordic" aliens that were said to resemble tall Scandanavian men. The percentage of sightings have declined, and when people do see UFOs, they don't land on the ground, and there's no sign of aliens.

Hammergren believes the lack of sightings means the public has become more cynical about UFO sightings.

"There are so many other things in the world to be puzzled about and worried about," Hammergren said. "Maybe this one is kind of staid and boring now. Every generation wants their own conspiracy, and there are plenty of other ones out there."

Even within CUFOS, there's no consensus on what UFOs actually are.

"It's absolutely a mystery, it absolutely should be investigated, and some intelligence is behind them, but I can't tell what that intelligence is. That's the three points we'd agree on," Rodeghier said. "Some of us would definitely say that aliens are here and they are causing some of the sightings. Others like myself are more on the fence, but I do know there are some things that are unexplained."

As an astronomer, Hammergren said he'd love to see evidence of UFOs but doesn't see enough to take it seriously.

"Most of the inquiries we get about UFOs are actually planets, bright stars on the horizon and things like that. The continued lack of evidence that would show we're being visited by extra-terrestrials, there's no scientific profit in it. If there was some hint of support or evidence, we would be jumping on that, we'd love to believe that because it would mean travel between the stars is possible and advanced civilizations would be possible," Hammergren said. "It's incredibly disappointing that there's not."

Ryan Smith is RedEye special contributor.

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