What are the Odds?

So, you’re standing there on the golf course at the last hole, waiting to sink your final putt of the game. The other members of your foursome have finished and it’s up to you to go for par. You bend over and take a practice putt, concentrating on the lie, the break, the distance to the hole, the wind speed, the time of day—all the factors that influence your putts.

Suddenly from out of nowhere comes a burned-out little piece of slag. It whooshes past your head and lands directly in the cup for a hole-in-one, shattering into pieces as it does so.

I logged into a discussion board earlier today and found the members all chattering up such a scenario, based on a story on today’s CNN.com: Space Station Cosmonaut ‘go’ for golf stunt.

Of course, being the pragmatic scientist (and former golfer) that I am, I felt constrained to point out that such a cosmic hole in one is pretty unlikely to happen. The biggest reason is that the golf ball is going to burn up in the atmosphere on its way down to Earth’s surface. Anything that’s left is going to be ash, or less.

But, just for fun, let’s imagine that some piece of the golf ball survives the trip. While the odds are against this happening, think about the variables in the problem.

First there’s the composition of the golf ball, which we assume meets at least some of the standards of the Royal and Ancient Golf Club of St. Andrews and the U.S. Golfing Association (which appears to be a world-wide standard). (Those standards are laid out here, if you’re interested.) The golf ball to be hit from the station will weigh considerably less than most regulation balls, coming in at only 3 grams, while regulation balls are heavier, but cannot weigh more than 45.9 grams.

Then, there’s the whole question of the construction of the golf ball to be used. It’s not mentioned in the story. However, a typical golf ball has a hard rubber core, a wound secondary layer (usually some kind of polymer), and a hard outer covering made of some kind of plastic. You know what happens to plastics when they are heated, so imagine this 3-gram ball slicing through our atmosphere, and the kind of friction it will encounter. (And, keep in mind that an incoming meteor (a rock!) of the same size as a golf ball is likely to burn up (although maybe not completely, depending the variables of its flight and its composition) on its way in.)

Other variables? We know the speed of the space station from which the golf ball will be hit, the rotation speed of Earth, the size and weight of the golf ball, and the gravitational pull it will feel as it comes down. What we don’t know is the strength of the cosmonaut’s swing, the direction he’ll hit it in, or whether or not he’ll slice it and send the ball whacking off some piece of the space station, thus changing its trajectory entirely. (Which reminds me of the last golf scramble I played in. My younger brother was part of the foursome and he has a hell of a swing. He stepped up to the tee, sliced the ball, sending it underneath the golf cart, where it swirled around and came shooting out the other side and hit a tree. Not only were WE staggering around laugh so hard it hurt, but the foursome of doctors behind us was howling in laughter, too. But I digress.)

A fun thought problem, but in reality the”Whack a Golf Ball off the Space Station” thing is just what CNN says it is—a publicity stunt to commemorate Alan Shepard whacking golf balls across the surface of the Moon during Apollo 14. It’s pretty unlikely that anybody on Earth will do more than hear about it on the evening news late on Thanksgiving Day this year.

But, if you’re a science teacher or somebody who likes to pose thought problems to people, this story might be a good way to teach a few basics in physics or strike up a heated discussion at a party.

Travel Pages Posted

In other news, we finally got our web pages up describing our trip to Australia and the tour of astronomy installations we made. While this was primarily a business trip, we did manage to have some fun and see some great stuff along the way. So, in the grand tradition of all those “What I did on my trip” stories, here’s a link to our trip pages:
Australia Trip Pages.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.