Bill Nye on Speaking to Aliens

https://www.youtube.com/watch?feature=player_embedded&v=TL1C-WoKuIk

My favorite class so far at the University of Oregon was Astronomy 123 (Expanding Universe). At the end of the term, I was surprised to find I had known nothing about the universe before that class.

One of the most revealing and memorable topics was life on other planets. We weren’t discussing microscopic life forms but intelligent life — life that’s had enough time to develop into the cognitive beings we’ve become on Earth — life we can communicate with using radio waves.

The only previous knowledge I had of “aliens” beforehand came from the multitude of science fiction movies, books and TV shows that depict them as planet-destroying monsters. So naturally I was skeptical of their existence, let alone their presence in the curriculum of a college class.

If before that class I had seen Bill Nye preparing what he would say to an alien, I would have thought it was a joke. After that lecture, however, fantasy morphed into a foregone conclusion in 80 minutes.

This diagram is only an estimation of intelligent civilizations such as ours in the Milky Way. Photo courtesy of physics.uoregon.edu.

The lecture included the “Drake Equation,” in which many factors are taken to estimate the number of other developed civilizations that exist in the Milky Way galaxy.

The pessimistic estimation of intelligent life on other planets was an insignificant fraction, leaving the likelihood of life in addition to that on Earth in our galaxy very small.

I remember thinking that the optimistic equation would probably yield less than five locations in our galaxy with intelligent life, at the very most. For one thing, we were only discussing our galaxy, which is just one of hundreds of billions. If the equation yielded, say, one planet harboring life in our galaxy, then by that calculation, hundreds of billions exist in the universe.

The equation assumed that conditions similar to those on Earth (such as distance from star and presence of water) are needed for intelligent life to develop. This substantially lessened the figure but likely made it more accurate. So I was floored when I saw the result of the optimistic calculation: 4,500. Over four thousand other planets in our galaxy may have developed the technology to communicate across solar systems.

Assuming the actual number is near the middle of the pessimistic and optimistic estimations (and assuming the figure holds for all galaxies), over two trillion unique planets harbor intelligent life.

Aliens are out there, and they’re all around us.

Near the end of that lecture, a student asked our professor what he thought of aliens, and whether it was safe to continue trying to contact them. I’ll never forget how he bluntly gave his opinion of what that type of revelation would mean.

“It would be the greatest discovery in human history,” he said. “We could exchange so much in terms of technology, medicine, histories. It would be beneficial for all of us.”

(For a more cautious opinion of contacting aliens given by Stephen Hawking, click here.)