What will you wear to Alpha Centauri? The news last week that there is a planet circling Alpha Centauri B, only a little more than four light-years away, set off an epidemic of daydreaming among the astronomical and sci-fi set.
For people who believe that interstellar voyages, either for people or for robots, are in the future, Alpha Centauri, a triple-star system that is the sun’s nearest known neighbor, has always loomed large and close as a destination. It was the home of the mythical jungle world Pandora in James Cameron’s epic “Avatar,” for example.
The new planet is a hellish unlivable blob of lava probably about the size of Earth, only 4 million miles from the fires of Alpha Centauri B, the second-brightest star in the system.
But if astronomers have learned anything over the past few years from devices such as the Kepler satellite, it is that small planets come in packs. There is plenty of room in the system for more planets, habitable ones.
“I think we should drop everything and send a probe there,” said Sara Seager, an astronomer at the Massachusetts Institute of Technology, echoing a call made last year by exoplanet pioneer Geoff Marcy of the University of California, Berkeley.
There is, in fact, somebody in charge of doing something just like that. She is Mae Jemison, a former astronaut, engineer, dancer, actor and entrepreneur. In conjunction with the nonprofit foundation Icarus Interstellar, she won a $500,000 government grant this year to set up 100 Year Starship, an organization to come up with a business plan for interstellar travel.
Jemison’s main work these days is spreading the word and raising money. The prospect of habitable real estate makes the idea of journeying to other stars that much more real, she said, adding: “This is a boon because most people have heard of Alpha Centauri. It’s close.”
Well, sort of close. There are 4.4 light-years — 27 trillion miles — from here to Alpha Centauri B.
We won’t get there by doing business as usual. Voyager 1, the fastest and most distant human artifact, is more than 11 billion miles from the sun and is speeding away at 11 miles per second; it would take 78,000 years to get to Alpha Centauri if it were going that way, which it is not.
Other schemes, based on existing or about-to-be-existing technology such as solar sails and thermonuclear rockets, have been proposed that could reach a tenth of the speed of light and make the crossing in less than a human lifetime.
Jemison was asked if she would go, knowing it was forever.
“Yeah,” she answered. “I would go.”
At a recent symposium, Jemison said, there was a lot of talk about what it means to be an interstellar civilization.
“Do we start calling ourselves Earthlings instead of Americans?” she asked.
So start shopping and packing — if you dare.
Presumably you won’t be limited to one carry-on.
