Scientists use increasingly precise technology to track near-Earth objects and gauge if a Cretaceous-style collision could be on the horizon. At the forefront of this research is MIT professor Richard Binzel, whose Museum lecture Asteroids: Friends or Foes? on Monday, April 16, evaluates the threat of asteroids and makes a case for how they might actually be useful to humans. Binzel recently answered a few questions about his research.
How do scientists monitor near-Earth asteroids, and how accurately can we predict collisions?
Richard Binzel: A number of different programs survey the sky each night. Once we’ve discovered and tracked an object for many months, we can reliably track it and predict close encounters several decades into the future. After tracking an asteroid for a number of years or refining our understanding of its position with a radar measurement, we can predict close encounters more than a century into the future.
Do any asteroids pose a threat to Earth in the near future?
Binzel: There is no asteroid currently known to be on a collision course with Earth. Boxcar-sized asteroids, and some that are larger, pass inside the orbit of the Moon many times a year. The most interesting will be a close pass by an aircraft carrier–sized asteroid named Apophis on April 13, 2029.
If the need ever arises, how might we deflect an asteroid?
Binzel: The most important factor would be advance warning time. The more time we have, the smaller any deflection would have to be to result in a certain miss. Hitting the asteroid or tugging it are possible solutions.
Are there ways we might use asteroids to our advantage?
Binzel: Some asteroids have up to 10 percent water in their minerals and might be a valuable resource for interplanetary astronauts. Others are metal-rich, and could perhaps be mined for building new structures in space. A few have proposed that bringing back metal-rich asteroids to Earth might even be profitable some day in the future.