Monday, February 19, 2007
Asteroids in the News
The weekly Kurzweil Accelerating-Intelligence News brings its usual roundup of sometimes strange, sometimes wonderful, sometimes scary bulletins from the cutting edge, with brief summaries that point you to the original articles. Retinal implants, self-assembling batteries, quantum computing, interstellar arks, and more. This New Scientist Space article on the threat of near-Earth asteroids is especially interesting.
Although the current estimate (1 in 45,000) for the probability of the 250 meter asteroid Apophis hitting Earth in 2036 may seem small, it is only one of many such asteroids, many of them still unknown (this cool JPL site lets you easily view animated orbital diagrams of potentially hazardous near-Earth objects, or NEO's - see Apophis here, the top picture above). It's not exactly that the sky is falling, but the threat is real, and asteroid impact is one of the few natural disasters that we might have a chance to do something about, if we continue to expand our tracking programs and if we develop the necessary technology.
The necessary technology doesn't require training Bruce Willis for a suicide mission (as in the rather silly Armegeddon) - it could be as (relatively) simple as parking a fairly massive unmanned spacecraft near the asteroid and allowing its tiny but long-acting gravitational pull on the asteroid to slowly "tug" it away from its collision course path. Of course this would have to be started while the asteroid is still quite far from Earth.
There are a few Orbiter add-ons that allow you to install and play around with some asteroids and the spacecraft that have visited or will visit them. One of them is the pictured ESA Rosetta spacecraft add-on by Brian Jones (search for rosetta2.zip at www.avsim.com). Here I have used the scenario editor to place it uncomfortably close to asteroid 2867 Steins (Java applet), which is also included in the add-on. Note that the gravitational effect of a spacecraft on a "body" (planet, moon, asteroid) is most likely not modeled in Orbiter, so you won't be able to try out the gravitational tractor idea yourself (at least not until some Orbiter add-on builder figures out a way).