Overhead Projector

McCain, in his ongoing campaign against government earmarks - $18 billion a year out of a $3 trillion budget - cites Obama's support for a $3 million earmark for an overhead projector. What's up with that? Well, it comes down to what you want to call things, and whether you think funding public education in science is wasteful spending.

This is what you and I would call an overhead projector. Depending on the model, it runs a few hundred dollars.



What Obama requested was money for a new star projector for the Adler Planetarium - kinda like this one:

Image Credit: Peter Maher, Alumni Relations, Wits University

A star projector is a multi-million dollar, multi-ton piece of precision optics and mechanics, combined with sophistocated and powerful computer hardware and other electronics. It is the device responsible for putting stars, planets, constellations, and other objects on the dome of a planetarium. The stars aren't just thrown willy-nilly, either, they are a nearly-exact representation of the night sky as one would see it at any time of night or day, at any location on the Earth. It should come as no surprise that I spent a fair bit of time at my local planetarium when I was growing up. There are a few thousand in the U.S. The Adler Planetarium in Chicago was the first in the western hemisphere, and remains one of the best in the world.

The star projector they are looking to replace has been around for 40 years, and the whole request is part of a $10 million renovation that combines public and private money. Over half of the planetarium's visitors are from outside the state, so federal funding certainly seems warranted. Incidentally, the $3 million request wasn't passed, so the planetarium is still looking for money.

There are many others that have a lot to say on the subject. Here are some links:

The Adler Planetarium's own response (pdf).
Professor Astronomy blog
NPR Talk of the Nation Science Friday segment.
Discover Magazine Bad Astronomy Blog
Comment in the NYT from Professor of Astronomy Andrey Kravtsov.