Update: Thanks to FoxNews.com's coverage of this event, the Journal of Cosmology reports an additional 100 volunteers for the voyage -- which was never taking submissions in the first place. Due to the volume of interest, the journal asks future volunteers, or those supporting a human mission to Mars, to e-mail OnwardtoMars@JournalofCosmology.com.

An interplanetary trip to Mars could take as little as 10 months, but returning would be virtually impossible -- making the voyage a form of self-imposed exile from Earth unlike anything else in human history.

What would inspire someone to volunteer? We've just found out.

A special edition of the Journal of Cosmology details exactly how a privately-funded, one-way mission to Mars could depart as soon as 20 years from now -- and it prompted more than 400 readers to volunteer as colonists.

"I've had a deep desire to explore the universe ever since I was a child and understood what a rocket was," Peter Greaves told FoxNews.com. Greaves is the father of three, and a jack-of-all-trades who started his own motorcycle dispatch company and fixes computers and engines on the side.

"I envision life on Mars to be stunning, frightening, lonely, quite cramped and busy," he told FoxNews.com. "Unlike Earth I wouldn't be able to sit by a stream or take in the view of nature's wonder, or hug a friend, or breath deeply the sweet smell of fresh air -- but my experience would be so different from all 6 to 7 billion human beings ... that in itself would make up for the things I left behind."

The psychological effect of space travel

Other volunteers include a 69-year old computer programmer, a college student at Texas A&M, and a 45-year-old nurse. Reverend Paul Gregersen, pastor of the Clarno Zion United Methodist Church, also said he would be willing to travel off-planet -- permanently.

"As the human race continues to expand, it only make sense to explore opportunities for human life out in the cosmos," Gregersen told FoxNews.com. "Also, I have the feeling that spiritual issues would come up among the crew. The early explorers on Earth always took clergy with them."

But more than spiritual issues will arise, warn psychologists who have worked with NASA.

"It's going to be a very long period of isolation and confinement," said Albert Harrison, who has studied astronaut psychology since the 1970s as a professor of psychology at UC Davis. He also warned that life on Mars wouldn't be as romantic as it sounded.

"After the excitement of blast-off, and after the initial landing on Mars, it will be very difficult to avoid depression. After all, one is breaking one’s connections with family, friends, and all things familiar," he told FoxNews.com.

"Each day will be pretty much like the rest. The environment, once the novelty wears off, is likely to be deadly boring. Despite being well prepared and fully equipped there are certain to be unanticipated problems that cannot be remedied. One by one the crew will get old, sick, and die-off."

All communications with Earth would also come with a delay of about 45 minutes. The volunteers said they are aware of the psychological issues, but believe they would be able to handle them.

"I've spent an inordinate amount of time with myself and my own thoughts, and am happy to do so till the end of days," Greaves said.

Are they qualified?

Volunteering is all well and good, but would Greaves or Gregersen have a chance of being selected? NASA spokesman James Hartsfield referred to the astronaut application guidelines posted on the agency's website.

Currently, the requirement of a college degree in science, engineering, or math -- followed by years of professional experience -- would probably disqualify most, he said. However, the mission in question is not intended to be sponsored by NASA. Harrison said he was more upbeat about the volunteers.

“The people within this group show high interest and would bring varied backgrounds and experiences to the mission,” he said. “Also, there will be spiritual issues to address, and it would not surprise me at all if the mission would benefit from someone who served as a chaplain.”

Currently, NASA astronauts must complete at least 4 to 5 years of training before going on long-duration missions. The training includes intense physical tests.

“Astronaut Candidates are required to complete military water survival before beginning their flying syllabus, and become SCUBA qualified to prepare them for spacewalk training,” the guidelines read.

Harrison said that he was sure good colonists could be found, but that political and regulatory hurdles would be a tougher issue.

"There will be tremendous public and political opposition from many members of the public to a mission which can only end in death ... There are people who can do the job, but the question is, will the public let them do it? I think to sell the missions, there has to be at least some chance of the astronauts returning."

The journey home

Harrison's comments raise an important issue: Why must this be a one-way mission? Why couldn't the brave few come back home?

“We prefer the one-way mission as it would drastically reduce costs,” said Dirk Schulze-Makuch, a professor at Washington State University who contributed to the Journal. His plan involves sending supplies to Mars as necessary, but not a return vehicle.

"The astronauts would be re-supplied on a periodic basis from Earth with basic necessities, but otherwise would be expected to become increasingly proficient at harvesting and utilizing resources available on Mars. Eventually the outpost would reach self-sufficiency, and then it could serve as a hub for a greatly expanded colonization program."

Given the difficulties of the mission, Lana Tao, the editor of the Journal, said she was surprised by the response.

"The e-mails volunteering were a complete surprise. At first we thought the e-mails were a joke, that volunteers were not serious. Then we received more and more with men giving their reasons and qualifications, and we realized they were completely serious."

Pasha Rostov, the 69-year old computer programmer, is serious about it.

"I do VERY well with solitude," he wrote of his qualifications. "I am handy with tools, very good at making things work, have generated my own solar energy, built three houses (with my own hands) and am quite sane and stable."

"And, I am ready to go to Mars. Sign me up," he wrote.