Creative Commons License Copyright © Michael Richmond. This work is licensed under a Creative Commons License.

Is there any way to deflect an asteroid?

We know that asteroids occasionally strike the Earth. Some are small enough to burn up before they reach the surface ...


Image taken from NASA | NPP Sees Aftermath of the Chelyabinsk Meteor

... and others are not.


Image of Barringer Crater courtesy of Google Maps

If a big asteroid were heading towards Earth, what could we do to deflect it? There are several possibilities, as the following video explains ...


Image from "Armageddon" taken from Vox Video Lab's description of NASA's efforts to deflect asteroids

One of the options is to place a spacecraft next to the asteroid and use the gravitational pull of the ship to accelerate the asteroid to the side.

For an asteroid of the size mentioned in the video, we could estimate its mass, and the distance to the spacecraft, as follows: 



   Mass of asteroid          M   =  3 x 109       kg

   Mass of ship              m   =  1 x 104       kg

   distance between          d   =  150           m 

   Gravitational constant    G   =  6.67 x 10-11  N*m2/kg2



      Q:  What is the size of the gravitational force on the asteroid?

My answer.

Huh? Could a force that small really change the path of an asteroid enough to prevent it from striking the Earth?

The answer is YES -- as long as one as enough TIME.

Creative Commons License Copyright © Michael Richmond. This work is licensed under a Creative Commons License.