December 19, 2012, 7:36 PM —
Source: Jaideep Khemani via Flickr
I've seen a few headlines about the habitable planet (or planets) orbiting a star called Tau Ceti in which the words "neighboring" and "nearby" were used.
OK, on a universal scale, 12 light years might qualify as "next door." But in terms of our ability to cover vast distances in space ... well, we just can't do it. And we won't be able to in our lifetimes.
The numbers are sobering. A light year measures 5.88 trillion miles. That's trillion, space fans. For some perspective, the moon is 240,000 miles from Earth, while Mars is (on average) 140 million miles from Earth. And it currently takes anywhere from six to nine months or so to travel to Mars.
To cover one light year -- or 5.88 trillion miles -- you would have to travel back and forth from Mars more than 40,000 times.
And that's just one light year. Our "neighboring" Earth-like planet orbiting Tau Ceti is 12 light years away. I looked around a bit online for how long it would take to travel a light year at current space-travel speeds. The number I kept coming up with was around 35,000 years. Multiply that by 12 and you discover it would take 420,000 years to reach Tau Ceti. How many times will the commander of that flight hear, "Are we there yet"?
Let's say I'm off on my multiplication and division (about a 50-50 shot) by a factor of 100: It still would take 4,200 years to reach Tau Ceti under current travel speeds. Does that really sound more doable?
The truth is, interstellar travel is a pipe dream until we find a radically new source of fuel or way to travel.
It turns out, though, that NASA is working on a faster-than-light "warp-drive" that would reduce a trip to Alpha Centauri -- the nearest star to our sun, about 4.3 light years away -- to a mere two weeks. So figure about six weeks to reach Tau Ceti.
Of course, this is all in the theoretical stage. There's a good article from late November on the science website io9 about NASA's efforts (including an interview with NASA physicist Harold White) that explains the warp concept:
It takes advantage of a quirk in the cosmological code that allows for the expansion and contraction of space-time, and could allow for hyper-fast travel between interstellar destinations. Essentially, the empty space behind a starship would be made to expand rapidly, pushing the craft in a forward direction — passengers would perceive it as movement despite the complete lack of acceleration.
Bottom line: They're working on it, but don't hold your breath. And don't run out and book a flight going beyond our solar system: You'll have a long, long wait.