Count Infinity

Alpha Centauri

In the time it took this page to load, a photon could have circled the entire earth 15 times. Light is the fastest thing in the universe; and, it so happens that (at least in empty space) the speed never varies. Because the speed of light is constant, it can be used to measure distances. One light-year is the (incredibly huge) distance that takes light one year to travel.

At these distances really funky things start to happen. It is just like in a thunderstorm when you see lightening and only later actually hear the thunder; because, it takes time for the sound to reach you. Similarly, if a star 500 light-years away goes supernova today our great great great grand children will still see the star burning bright in the sky, even though it died hundreds of years ago. We can see stars today that burned out before the dinosaurs went extinct because they are millions of light-years away. If aliens millions of light-years away have awesome telescope technology, they might be looking at our planet right now and freaking out about T-Rex’s impressive grill.

What does this have to do with Alpha Centauri? Everything really. Alpha Centauri is a star system with two stars (‘A’ and ‘B’) tightly orbiting each other. There is a third (and likely related) star nearby named Proxima Centauri. These three stars are all about 4 light-years away, and are the closest stars to our sun.

:Drumroll: Cue the impossible…

4 light-years is incredibly far. It takes light 4 years to make the journey, and we’re not even remotely close to reaching those kinds of speeds. Ages ago we launched the Voyager 1 spacecraft. It’s traveling at a cool 17085 meters per second, which is about 0.006% of the speed of light. At that rate it would take Voyager 74399 years to reach Proxima Centauri, and another 3684 longer to get from there to Alpha Centauri. Most people will agree that given the vast distance, and our current level of technology, it is impossible for us to travel this distance in a lifetime.

I reject the impossible. Not only can we travel this distance, but we do, and we have been for years.

One of the great things about the USA is that we have a bureau for everything. Investigation? Sure! Tea Tasting? Had that too until some nitwit axed it. I recently found an awesome one called the “Bureau of Transportation Statistics”. Sounds lame until you get it in your head to look for funky information like the number of miles driven each year going back for forever. I suddenly appreciate random worthless government agencies (at least a little).

As it turns out, lately America drives a light-year about every 2.5 years. Between 1994 and 2003 (the last year I have actual data for) America drove 26,441,018,000,000 miles. Convert to light-years and that’s an impressive 4.5 light-years. A road trip to Alpha Centauri, with a stop at Proxima Centauri on the way, would put only 4.45 light-years on your car.

This is the new normal. I extrapolated the data, and it looks like by the end of 2010 the USA will have driven 15 light-years since 1960, with half of that in just the last 15 years.

Traveling 4 light-years isn’t something to aspire to, we’ve been there, done that; and, we did it 100% on fossil fuels, in an atmosphere, with friction and gravity fighting us every step of the way. We totally rock!

Extra reading (AKA, “sources”)

1. http://voyager.jpl.nasa.gov/mission/interstellar.html
2. http://www.bts.gov/publications/national_transportation_statistics/2004/html/table_01_32.html
3. http://en.wikipedia.org/wiki/Alpha_Centauri
4. http://en.wikipedia.org/wiki/Light-year