After a drink or two, having sex is a natural inclination. Will the lack of gravity be a problem? (It could lead to some interesting "positions"). A trip to even one of our closest stars would take decades and possibly even hundreds of years, spanning multiple generations.
But scientists aren't sure humans can procreate safely in the microgravity of space. So far, humans haven't managed to send a probe beyond even our own solar system, let alone to the nearest star more than 4 light-years away. A light-year, the distance light travels in a single year, is about 6 trillion miles.
In LiveScience.com, Clara Moskowitz quotes MIT researcher Dan Buckland as saying, "It is still unknown, if you want kids and you want reproduction, what gravity has to do with successful development."
But even if they're up for it, will they be strong enough to do it? Unless scientists can invent a practical method of simulating gravity on a spacecraft, an interstellar journey would be spent in weightlessness. Over time, microgravity ravages the body, decreasing blood volume, atrophying muscles, diminishing bone mineral content and impairing vision. Moskowitz quotes biologist Athena Andreadis as saying, "The distances to the stars at vast. Large starships will have to be self-sustainable. We don't have such technology yet."
And then there's the inevitable result: Moskowitz quotes Andreadis as saying, "Giving birth in zero gravity is going to be hell because gravity helps you" on the ground. "You rely on the weight of the baby (to push the infant out)."
Who knows what the future will bring--will babies born in space be hybrids? According to Andreadis, "We will have to grow up and do self-directed evolution, realizing that what comes out of the other end may not be human." Whitley Strieber created these extraordinary beings in fiction. This novel is out of print, so you won't find it in your bookstore, but you can still get it (along with an autographed bookplate designed by Whitley) from the Whitley Strieber Collection!