Tuesday, September 27, 2011
The power of dumb questions
Fun fact: back in the summer of 1999 I, Prof. Johnson, was a SURF student working in the LIGO group for Prof. Libbrecht and Dr. Phil Willems. It's crazy to me that these great scientists are now my peers! But it's proof positive that SURFers go on to do great things.
One of my most vivid memories from that summer took place in the basement of Robinson Hall. I went to visit a fellow SURF student on whom I had a crush. In her office was a poster of M33, not unlike the one pictured here. After staring at it for half a minute, I asked her A Stupid Question: "Um, what are all these really big, bright stars outside of the galaxy? Fortunately, my fellow SURF student didn't roll her eyes, or laugh, or sigh.
Instead, she jumped up from her chair and seized the opportunity to teach a fellow student about something she was passionate about. She told me that the big stars were actually normal-sized, but that they were closer and in our own Galaxy. In the picture, we were looking past stars in the Solar Neighborhood, out through our galaxy, and into a very distant galaxy composed of stars so far away and so numerous that they blurred into structure of what we call M33.
At first I was embarrassed that I had overlooked such an obvious explanation. But then, suddenly, right before my eyes the image of M33 took on a three-dimensional shape that I had never seen before in an astronomical image. For the first time, I sensed the structure of the Milky Way. I felt how enormous it is. I realized how gigantic M33 really is. HFS, I can see!
This event illustrates the power of "stupid" questions. Stupid, obvious questions are my favorite variety. Science works when people challenge the obvious, revisit "old" knowledge that everyone "knows," and ask dumb questions. Please keep this story in mind during the semester and let it guide how you approach Ay20.
Let me start off asking a dumb question about the image of M33. Take a look at some of those foreground stars. Those stars are points of light, with no discernable dimension. The only reason they have any shape is due to the limitations inherent in the optics we use to view them. They are point sources. And yet, any astronomer will tell you that we know a great deal about those tiny points of light. We can measure their temperatures, radii, masses, magnetic fields, chemical compositions and search for planets around them. We know a bit about how they form, why they shine, how long they'll live, what their internal structures look like.
The dumb question that forms the basis of Ay20 this term is: Seriously? Are you seriously telling me we can know all of this from a point of light in the night sky?
Do you buy it? You shouldn't at this point. But by December I think you will, and I hope you'll remain as amazed as I am about it!