How to avert an asteroid disaster? Just give it a tow

[emad]

Times
By Nigel Hawkes



NO NEED to despatch Bruce Willis into space with a nuclear bomb and a drill: the best way to deal with an asteroid hurtling towards Earth is gently.

Two Nasa astronauts, obviously unimpressed with the plot of the 1998 film Armageddon, say that a better solution would be to tow the asteroid out of the way using nature’s weakest force, gravity. Edward Lu, who studied applied physics at Stanford University, and Stanley Love, an expert on the collisional evolution of asteroids, propose in Nature that a 20-tonne unmanned satellite be launched if an Earth-crossing asteroid were detected. Such asteroids have the capacity to plunge the Earth into a long, dark winter.

The impact can often be predicted years or even decades in advance, from a precise knowledge of the asteroid’s orbit. So there is time to act; the discussion is about what best to do.

Asteroids are rough lumps of rubble loosely held together, the two astronauts write. That makes landing on them or tethering anything to them very tricky. Simply pushing them out of their orbit is difficult because they are in constant rotation. That means the spin would have to be arrested, or force exerted only at certain moments during the rotation, to achieve the desired effect.

http://www.timesonline.co.uk/article/0,,3-1865267,00.html


NB Posted on GD because a bug prevents me accessing Science forum. Bug reported. Thanks, Emad.

[Ptah]

1. Astronomy picture of the day!

http://antwrp.gsfc.nasa.gov/apod/ap051110.html

[emad]

2. Maybe that's the gigantic diamond asteroid in the sky that the UK

press reported some years ago, caliming the Russians were already trying to send a probe equipped with drilling equipment, to ransack it....

Expect DeBeers already claims it as a franchise....

[TlalocW]

3. I read something where it was proposed

That it made as much sense to send a team of champion bowlers in a ship with a bowling alley that when a bowler rolled a ball down the lane, instead of hitting pins, it would be shot out the front of the ship towards the approaching asteroid.

Since the ball would be traveling at the speed of the ship plus whatever extra speed the bowler threw it, and frictionless space wouldn't slow it down, they would do quite a bit of damage.

But then I liked "Armageddon," for the simple reason that Bruce Willis dies in it. Any movie like that is okay with me.

TlalocW

[KansDem]

4. Well, there's a catch to this...

The impact can often be predicted years or even decades in advance, from a precise knowledge of the asteroid’s orbit. So there is time to act...

Not if Bush, or a Bush wannabee, is in the White House:

"Mr. President, an asteroid is predicted to hit us in xyz years!"

"(yawn) Don't bother me now! I'm strumming on this guitar!"

"But Mr. President, although this catastrophe won't happen for another xyz years, the time to act is now! We must plan!"

(trying to pick some food out from between his teeth with his fingernail) "I said 'Don't bother me!' I'm going to eat some cake now!"

"But, scientists are warning us that we must act!"

"Huh, did you say 'scientists?' (picking at some earwax) Are these 'old scientists' or are they the 'new ones'"

"I don't know. They could be ones who have recently entered the field."

"That would be 'Intelligent Design'-type scientists. Don't worry. Let the Intelligent Designer handle this problem. I'll talk to him tonight, right after my bike ride!"

[quaoar]

5. We're safe from asteroids for the time being

Any asteroid that was about to hit Earth would notice the destruction caused by the Bush Administration, assume that this planet had already been hit by an asteroid and move on to another target.