When almost the first word a child says, as she points to the night sky, is `` moon,'' you feel duty-bound to cultivate that interest, if not to start putting aside tuition money for Young Astronauts Camp. So on the 40th anniversary of the first Apollo landing, I was happy to watch, with my granddaughter Julia, age 9, NASA-channel films of the manned moon missions.

I was in for a shocking epiphany.

The documentary got to the Apollo 13 mission, the one we almost lost. First came the iconic, understated SOS, ``Houston, we've had a problem.'' Next, with the outbound explosion-ripped spacecraft operating on standby power 200,000 miles from Earth, and three astronauts facing live burial in the graveyard of infinity, the scene switched to Mission Control, where knots of somber men huddled to determine how to save lives, if not the mission.

The next scene -- the jolter -- was a close-up of an engineer doing his bit to bring the astronauts back. On a sheet of paper, this man was furiously making complex calculations with a pencil. America's perfect record of never having lost a man in space hung partly on the scratchings of No. 2 lead and the crisis-tested acumen of a man who had devoted his professional life to mastering knowledge that now repaid that devotion with the crucial Right Answer. Astronauts James A. Lovell, Jack Swigert and Fred Haise would be coming home.

At that moment, the men with the flattops, short-sleeve white shirts and pocket protectors were, hands down, the most heroic figures on the planet. The crucial question: Is the United States still producing such people? People with exactly the right stuff in the most wrong of circumstances?

That America has a deep bench of brave, capable astronauts I have little doubt. The first U.S. spacemen were test pilots, not super scientists. They were good with machines that could outrace sound, and they could perform coolly in a crisis that required judgment and reflexes working so closely together they were essentially one. Such virtues today are regularly demonstrated by Americans, in other life-and-death situations, in all the military services. The talent deficit lies elsewhere.

It's the hyper-focused, monastically dutiful nerd, indispensable to any manned space mission, whose existence in meaningful numbers I doubt.

First, the statistics on U.S. education are disquieting. The Third International Mathematics and Science Study (TIMSS), testing a half-million K12 students in 41 countries, finds that in math by Grade 12, U.S. students rank 19th of the 21 nations reporting results (Asian students wrap up the tested math curricula before 12th grade), behind every listed European country. Our young scholars best tah-dah! Cyprus and South Africa. In science, U.S. kids rank 16th of 21.

A common criticism of such comparisons is that they set all U.S. students against elite foreign ones. This study controls for that. Also, when the best U.S. 12th-graders take on the best of 15 other nations, the Americans finish next to last in math and ride the caboose in science. Few of our shining lights are good candidates to one day do lightning-quick logarithms on a notepad capable of saving maydaying rocket men.

But what about when our best students get to our world-renowned colleges? Don't they measure up then? Ominously, a 2008 report of the Congressional Research Service finds that ``(e)nrollment of U.S. citizens in graduate science and engineering programs has not kept pace with that of foreign students in those programs.'' In 2005, foreign students earned about 35 percent of doctoral degrees in science and 63 percent of the doctorates in engineering.'' Among such students, Chinese postgraduates capture a plurality of Ph.D.s in these fields. Moreover, most high-credential aliens don't put down roots in the United States: Only one in 10 claims permanent resident status.