Editor's note: Meg Urry is the Israel Munson professor of physics and astronomy and chairwoman of the Department of Physics at Yale University. She is also the director of the Yale Center for Astronomy and Astrophysics.
(CNN) -- Did you hear about the 6-ton NASA satellite expected to fall to on Earth on Friday?
Don't panic, Chicken Little! All kinds of space debris -- both man-made and natural -- falls harmlessly to Earth each year, and like those bits and pieces, the debris of this satellite will probably fall into the oceans or onto uninhabited land. NASA puts the odds you will be hit by debris at 21 trillion to one.
Still, this event is an example of the technical challenges humans continually face. In this case, engineers calculate orbits, experts with math skills estimate the odds of being hit, and scientists characterize the atmosphere that drags the satellite down, and presto: We have information to guide our choices (and reassurance to calm our fears).
Almost any current issue -- natural disasters, terrorism, energy, global competition, the economy -- has some connection to science, technology, engineering or math (the "STEM" fields). According to a report from the National Academy of Sciences, "as much as 85% of measured growth in U.S. income per capita was due to technological change."
Societies that lead in STEM expertise therefore have an increasingly important edge. But not enough scientists, engineers and mathematicians are currently being educated in the U.S.
Our colleges and universities graduate many more business majors than engineers and many more political science majors than physics majors. Three times as many college seniors plan to be artists as plan to be research scientists, according to UCLA's Higher Education Research Institute. Of course, the arts, humanities and social sciences enrich and inform our lives. But it is worrying that the United States consistently ranks in the bottom third of developed nations for math and science literacy.
Fewer than 15% of U.S. high school graduates have the background to pursue college degrees in STEM fields, and fewer still actually do.
In 2005, most U.S. doctorates in engineering, math, computer science, physics and economics went to foreign citizens. I don't mean to sound xenophobic -- the U.S. gains enormously from open exchange of information among nations -- but it isn't clear the U.S. will retain and benefit from this STEM talent.
Meanwhile, Europe and Asia are producing far more engineers and scientists than the U.S. To be sure, not every engineer and scientist trained abroad is equivalent to an MIT graduate, as pointed out in a recent study from Duke, but it is clear we are falling behind.
So who's the culprit here?
It's at least partly us: college teachers. Many science professors believe that their subjects are just too hard and that the weaker students drop out. But classic studies by Sheila Tobias and by Elaine Seymour and Nancy Hewitt showed this is wrong: that the students who leave are as smart as those who stay and that the reasons are more varied.
As a high school student many years ago, I found physics far less engaging than English and history. Freshman physics in college was no better: It addressed overly simple systems, quite unlike the real world, and I couldn't see how the laws of physics were helpful to anyone. Tobias' students said much the same.
Ours was a classic reaction to the fact that science classes often lack context. "There is so much material to cover in so little time," science teachers lament, that they can't take the time to explain the purpose of what they are teaching.
And science classes can be very dry. If you don't instantly love them, you need motivation to keep going. "Intro physics," I now tell my students, "is like learning Italian grammar so that you can eventually read 'The Divine Comedy.' " It's a tool you need to work on the really fun stuff.
I began to love physics during my first research experience, when I spent a college summer helping an astronomer at the National Radio Astronomy Observatory find powerful radio-emitting galaxies ("quasars"), objects that are powered by the gravitational energy of a supermassive black hole. Here was real physics, and it blew my mind!
I still remember seeing the first "gravitational lens" -- multiple images of a distant quasar whose light is bent by the gravity of intervening matter, much as glass bends light. At the time, I didn't know what a gravitational lens was, and I sure didn't know I was looking at one, though years later it seems extremely obvious. Still, the thrill of scientific discovery had me hooked.
Like me, college students may plow through many science classes before getting an opportunity to do research. So "chalk and talk" lectures need to evolve. Research shows that science students benefit from more interactive classes. Some teachers, including me, have started using electronic "clickers" to allow back-and-forth with students, just like the audience voting in "Who Wants to Be a Millionaire." We have also updated curricula to connect more clearly with real-life issues and provided group tutoring to overcome student frustration. We should and will do more.
Because the bottom line is this: Our society benefits from having the best brains working on the toughest problems. This means keeping students interested in STEM subjects, training more STEM-proficient teachers, producing more scientists and engineers and helping all of our citizens to be STEM-literate. If we don't do this, maybe the sky will fall in.
The opinions expressed in this commentary are solely those of Meg Urry.