Saving a Single Life – Asteroids??

About 11 years ago, Gregory Benford, noted science fiction author and physicist (on the faculty of the Department of Physics and Astronomy at the University of California, Irvine) wrote in a column that saving a single life in 1995 dollars would cost

• $200, in third world countries (usually due to malnutrition)
• $75,000, in advanced nations (cancer screening)
• $120,000, in USA (highway safety agencies, better highway dividers, easier on-ramps, etc.)
• $1,000,000, in USA (to avoid one case of deadly lung disease by having better air pollution controls)
• $5,000,000, in USA (to eliminate natural radioactivity in drinking water, which is why we don’t do it)
• $2,500,000,000, in USA (for nuclear plant safety)
• For about 600 times the cancer screening rate, or $50,000,000 per year, killer asteroids could be identified and eliminated from threatening the earth.

This last point has always intrigued me, particularly when that Bruce Willis movie came out a couple of years ago.

The ABC Science Show had an interview with Sima Adhya, a space mission scientist at QinetiQ in Great Britain. This interview aired September 23, in which the asteroid proposition was again discussed, but in more current terms and with some ideas about how to actually do something like this, Hollywood not withstanding.

A link to the transcript and podcast of that broadcast is herehttp://www.abc.net.au/rn/scienceshow/stories/2006/1744501.htmand herehttp://www.abc.net.au/rn/podcast/feeds/ssw_20060923.mp3

The European Space Agency is planning to send two spacecraft in about 5 years to an asteroid about 30 million miles away. It will take another 5 years after launch to get to the asteroid. So from Benford’s earlier notation to now, 11 years passes. In 10-11 more years we shall find out some other things about this particular issue.

The plan is to have one spacecraft go into orbit around the target asteroid. It will be in charge of measuring the mass, density, finer details on it’s speed and direction, and other information about the asteroid. The second spacecraft (which will be about the size of a refrigerator) will crash into the asteroid (about 100 meters long) while the first one will watch, taking even more measurements.

In this David and Goliath move, scientists are hoping to alter the orbit of the asteroid by a very, very small amount. According to this interview, the expectation is a few millimeters per second, but at 30 million miles away, this event and the alteration will add up over time and distance. If the asteroid were indeed on a collision course with the Earth, such a minute adjustment in direction would allow the asteroid to miss the Earth completely.

As a prototype proposal for activity they are actually proceeding with, I’m impressed with the European scientific community.

But more to the point, if this works, then obviously real money estimates will come out of the exercise. Ultimately we may see if Benford’s estimates were in the ball park or not. Commercial interests might include reduction of risk on the part of the insurance industry. I’m sure they’d rather fund a space flight so that in 5 years a killer asteroid might be deflected and thus reduce to nil any claims at all from such a tragedy.

Perhaps the biggest problem is convincing anyone to actually do the kind of follow-up activities needed. The odds of an extinction level event are so small, and because of this, it is assumed that these odds are zero, when in fact they are just very close to zero. My sense is that this low risk will always be weighed against actually doing something.

Of course, the other thought is that we would rather be living here without a dinosaur type extinction event, no matter what, than try to live here after one…