Dangerous Secrecy

NASA is getting itself into deep trouble over its plans to deflect dangerous asteroids. It has been accused of obstinately persisting in the reckless course of trying to destroy them with nuclear explosions. More serious still, according to the distinguished space hazard expert Clark Chapman, the agency is guilty of secretiveness. ``When I questioned [their plans] at Nasa headquarters, I was told that the nuclear options are top secret and not for public discussion.'' [ See his views at www.boulder.swri.edu/~cchapman ] This is a complete reversal of Nasa management policy from that which prevailed before and during the Moon landings. In those days the agency believed in complete openness. Nothing was to be hidden from the public.
The people who created Nasa in 1958 created a managerial revolution that transcended all previous theories and techniques about the administration of large projects. In doing this they were much influenced by the hatred of secrecy felt by J. Robert Oppenheimer, father of the atomic bomb. This is a story that should never be forgotten. When Oppenheimer was accused by McCarthyite Senators of being indiscreet about aspects of atomic power which they thought should be kept secret, he turned on them fiercely: "We do not believe that any group of men is adequate enough or wise enough to operate without scrutiny or without criticism. We know that the only way to avoid error is to detect it, and that the only way to detect it is to be free to enquire. We know that in secrecy error undetected will flourish and subvert.'' If this policy of frankness and honesty were to prevail today, people might start to suspect that the idea of nuking threatening asteroids, however entertaining that may be in Hollywood movies, would in real life be the most dangerous method of preventing them from colliding with Earth. Instead of removing hazards it would be likely to multiply them. For asteroids, being objects of low mass, have very weak internal gravity. If exploded they would shatter, and instead of one object striking Earth there would be many. These fragments could do far more damage than the original intact object. There are far simpler ways to do the job, provided the asteroid is detected in time. An object that is found to be on a collision course with our planet could simply be deflected. This would involve changing its course with a sideways push so that it arrives either before or after the moment when it crosses Earth in its orbit. If carried out years or decades before the predicted impact, such a measure would be highly effective. Let us say that a dangerous asteroid three or four miles wide is spotted 20 years before it is due to strike. A nudge to change its speed by just one mile per hour would alter its location in space by a safe distance of 170,000 miles. While there's no evidence of any future threat from giant civilisation‑destroying asteroids, there is plenty of menace from smaller ones that could wipe out a major city. How easy it would be to prevent such a tragedy if only Nasa could remember and return to the cultural origins that launched it so brilliantly.