COMMENTARY | While NASA and its space partners are still dithering over where they want to send astronaut explorers to next, back to the moon or to an asteroid as President Obama wants, the Chinese are exploring a different kind of asteroid mission.
The Chinese have selected a 10 meter diameter rock named 2008EA9 that is scheduled to pass about a million kilometers from the Earth in the year 2049. The idea is to alter the asteroid's path ever so slightly to bring it into orbit around the Earth.
Contrary to the NASA plan to send astronauts millions of kilometers and weeks into space to rendezvous and dock with an asteroid, the Chinese propose to bring an asteroid closer to Earth and then visit it at leisure. The specific plan would involve 2008EA9 being in a temporary orbit twice the distance from the Earth as the moon; it would wander away after a few years.
The Chinese plan would solve several of the problems involved in an asteroid mission described by planetary scientist Paul Spudis in a recent piece on the operational difficulties of undertaking an asteroid mission. Astronauts would not be obliged to expose themselves to the hazards of radiation and microgravity for weeks while traveling to an asteroid. An asteroid in a high orbit around the Earth could be visited multiple times, at leisure, whereas a visit to an Earth approaching asteroid while still in a solar orbit would be by necessity limited because of the astronauts would have to voyage to the rock and then return in short order.
The tendency of asteroids to spin and tumble still present a problem, especially when altering their course and speed are involved. Some way would have to be found to "despin" the asteroid no matter how one explores it if one proposes to actually dock with it.
Still, the Chinese approach has several virtues.
First, right away, the experience gained changing an asteroid's course would be useful if one is detected headed on a collision course with the Earth. NASA is not contemplating practicing those kinds of techniques, at least for the near term. Of course if the Chinese miscalculate, even by a little, a deep impact scenario might take place by accident.
Diverting an asteroid and putting it into a safe orbit would also be useful if one proposed to mine it. Trying to mine an asteroid while still in a solar orbit would be perhaps too challenging. If the rock is easily accessible from the Earth or from a lunar settlement, potentially trillions of dollars in resources could be obtained, a tempting prospect to say the least.
Mark R. Whittington is the author of Children of Apollo and The Last Moonwalker . He has written on space subjects for a variety of periodicals, including The Houston Chronicle, The Washington Post, USA Today, the L.A. Times, and The Weekly Standard.
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