Sunday, June 5, 2011

An Ignorant Dispatch to the Stars

The Pioneer plaques were attached to the Pioneer 10 and 11 spacecraft, which are already about twice as far from the Sun as Pluto. Though they ran out of fuel long ago, the two spacecraft have enough velocity to completely escape from the Solar System. They will wander amongst the stars in the eons to come, their gold-covered plaques hitching a ride. The idea behind the plaques was to communicate information about humanity should the spacecraft be intercepted by extraterrestrials. Of course, such information must be culture-neutral if it is to be readily understood by an alien race. Simple drawings of our bodies and solar system made up the plaque.

Pioneer plaque
The Pioneer plaque
There is one piece of information on the plaque that should begin to strike us as odd. The bottom contains a linear progression of circles, the first being much larger than the rest. These obviously represent our sun and planets. The next four circles are small, like the terrestrials planets, and the four after those are larger, like the gas giants. But why is there a ninth planet that is as small as the first four?

Our initial inclusion of Pluto as a planet is an example of our failure to group objects by their characteristics. Neil deGrasse Tyson, an American astrophysicist, advocates looking at commonalities between astronomical objects and moving away from simply counting the planets. He sees the terrestrial planets as one group, the gas giants as a second, and Pluto and like objects as a third. This makes a great deal of sense to me. It's too bad the reclassification of Pluto by the International Astronomical Union didn't happen before the Pioneer plaques were dispatched to the stars. What might an extraterrestrial think after looking at that ninth circle?

No comments:

Post a Comment