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Neil deGrasse Tyson On How To Stop a Meteor Hitting the Earth
An anonymous reader writes "Astrophysicist Neil deGrasse Tyson talks stopping extinction-level meteor hits: '...Here in America, we're really good at blowing stuff up and less good at knowing where the pieces land, you know...So, people who have studied the problem generally – and I'm in this camp – see a deflection scenario is more sound and more controllable. So if this is the asteroid and it's sort of headed toward us, one way is you send up a space ship and they'll both feel each other. And the space ship hovers. And they'll both feel each other's gravity. And they want to sort of drift toward one another. But you don't let that happen. You set off little retro rockets that prevent it. And the act of doing so slowly tugs the asteroid into a new orbit.'"
I'm going to assume Astrophysicist Neil deGrasse Tyson is a much better source than you.
I agree, he's great for explaining stupid shit to proles, but as far as a professional scientist goes he has very little credibility in my book.
Great. You'd be comfortable with this future:
Scientists: By the way, there is a huge hunk of rock that is going to hit the earth tomorrow and wipe us all out.
Public: Wait - what? Why didn't you warn us?
Scientists: We discussed it at length at our obscure meetings. Why should we have to take time out of our important work to explain complicated shit in your terms? Stupid proles.
If Slashdot were chemistry it would look like this:Cadaverine
Why do you say that? He's an established scientist and has a Bachelors in Physics and a Graduate/PH-D in Astrophysics. He's held positions at several universities and is the director of the Hayden Planetarium. Sure he goes on television more than your average physicist, but so did Carl Sagan. He's charismatic, and it works well for him. Nothing wrong with that.
Dr. Phil is a pool of waste that puts people on television and exposes their issues to millions of viewers, for the ratings and a fat pay check. He doesn't add anything to his profession, and his discussions on television don't enlighten anyone.
There's a huge difference.
The asteroidmay not be solid rock. It could be a rubble-pile type, and there might not be anything solid-enough to apply force to in a consistent way. It might be two closely orbiting bodies of rock, in which case you can't push on one in any type of consistent direction.
The benefit of the gravity-tug approach is that if you have a body of some concentrated mass moving at you, then if you have a spaceship sit away from it and maintain a constant position relative to a point other then the asteroid, then you can act on it's entire mass consistently.
Find it early enough, and you can do this with high-efficiency ion thrusters, rather then needing inefficient chemical rockets.
Re: reactive force from retrorockets - you fire them off-angle to the asteroid so exhaust doesn't hit them. You can easily mount orthogonal engines which would carefully cancel the attraction of the asteroid without directing any exhaust at it.
I usually welcome hearing Tyson's latest addition to lay science understanding.
I sort of like character-celebrity-scientists. Mister Wizard, Bill Nye, and local college instructor / news-show scientist "Chemical Kim" are just a few of the scientists I applaud for their work in bringing science to the masses as a fun and interesting subject.
I don't like the stand-in experts like Michiu Kaku or Tyson, who take a different tack of bringing science to just a large audience, not really packaged for the masses at all, often with their own opinions added, and typically very pompously presented.
Tyson manages to keep my respect by being relatively sane and mainstream, basing his conclusions and projections on "establishment" science.
I can't say the same for Kaku, who I haven't heard from in awhile because I purposefully stop visiting web sites and stop listening to radio shows that give him a podium (no, this is not a viable way to get me to stop visiting /.)
But Tyson also manages to capture my interest by doing the same thing Bill Nye does: making comments about human affairs and human nature. They both humanize science.
But Tyson's pomposity sort of makes it hard for me to "like" him. And I just read something about him recently, so now it's like a second serving of buttered scallops when I clearly had trouble finishing the first serving.
"Stratigraphically the origin of agriculture and thermonuclear destruction will appear essentially simultaneous" -- Lee
Because we are currently unable to judge the stability of the object, or it's internal mass distribution just by looking at it from long range.
Pushing it at any point might just lead to breaking off a small piece, or the spaceship slowly sinking into and through it.
If we miss the mass center, the push will mostly be transformed into rotation.
All these problems are a non issue with gravitiational pull.
Even if it wasn't the case, it seems to be it would be a hellva lot more efficient to use the rockets to just push the damn asteroid, rather than rely on gravity. A couple of tonnes of probe isn't going to exert much influence on a couple of hundred (thosand?) tonnes of space rock.
You don't need much deflection if you have enough time.