Posted on 11/17/2007 2:07:34 PM PST by blam
Deflected asteroids may keep coming back
17 November 2007
What goes around comes around. Unfortunately, no such karma figures in plans to deflect asteroids on a collision course with Earth, a hearing of the US House Science and Technology Committee was told last week. One big whack will deflect an asteroid temporarily, but does not guarantee safety next time its orbit brings it close.
Asteroid researchers have long debated the merits of deflecting asteroids with a powerful blast such as a nuclear explosion. However, Rusty Schweickart, who heads an asteroid research group called the B612 Foundation, told the committee that the effects of powerful blasts are hard to predict, especially if Earth's gravitational pull acts on the object. An asteroid could pass through one of the "keyholes" that would nudge it back onto a collision course, so once diverted it might need to be steered past Earth to prevent this.
(Excerpt) Read more at space.newscientist.com ...
Mass is always an issue if you want to move it.
{[He whines]}”but that will cost money that would be better seized by uncle gov’t to pay for my welfare check” {[Whine off]}
Seriously, that makes sense, but will never happen through the auspices of gov’t, at least not so long as “We. the People” think the purpose of gov’t is to take from those who have more, and give to “me”.
We get exactly the government we want, whether or not it is the government we should have.. Thats why the founding fathers said that in order for any system of self government to survive, the electorate must be moral AND educated. Pity that we are no longer neither.
Now there’s an idea, make the welfare check dependent on getting training and being one of the colonists on the ship/station.
Obviously but with enough lead time you only have to move it a little at a time.
They are not looking at the mineral value of these gifts of the cosmos. An asteroid could be captured if they wanted.
Picture a bunker buster. The nuke drives into the asteroid and explodes, a small portion of the asteroid ejects at very high speed in the form of gas and rubble. This force is matched by the rest of the asteroid moving very slowly in the opposite direction.
The fear is that the asteroid is frangible and you end end up with a pile of rubble heading towards earth like a shotgun blast.
Any blast causes damage by extreme overpressure on exposed objects. A pulse of force.
Must be something in the detonation that lifts the target into the upper stratosphere. The problem is that asteroids are now seen better and appear to be loose piles of rubble rather than solid objects so a detonation would create several smaller piles still on roughly the same course. Would it be better to spread the collision with earth over an area or let it hit a small area?
Excellent cost-effective solution!
Once the orbit of an asteroid is determined it may be that a lot of options would be available. There are points in an orbit that are extremely sensitive to an external push. These Legandre points are balance points between influential gravitational bodies. Push a little bit at one of these points, and one can redirect enormously, the future path of the asteroid. Astronomical Ju-Jitsu.
I forgot about global warming! You’re right—no problem!
Either Mr Schweickart’s orbital mechanics skills have suffered over the years or the Global Warming faithful at the New Scientist have chosen to misinterpret his testimony in order to promote yet another “End Of The World!!!” cult based on junk science.
To capture requires two impulses. The first impulse changes the orbit so it has the required apogee and the second, some time later when the asteroid has arrived in the right place but wrong velocity, changes the velocity so apogee and perigee are correct. The asteroid will then be in orbit around earth where it may be picked over later at some convenient time.
Are we talking about detonations near the body or impulses from reaction motors attached to the surface?
keep in mind that many asteroids are really low density flying rock piles.
I would put ion motors on the body and apply continuous thrust, which means an infinite series of impulses rather than just two. This would keep the pile more or less intact. It’s similar in effect to the two impulse method as far as orbital mechanics goes, although much slower.
Astronaut Russell ‘Rusty’ Schweickart was the Lunar Module Pilot for Apollo 9.
All right, we can get there with an Ares rocket (if it ever flies that is). Vaporize it how? Capture the vapor in what? form the sail by what means? Navigate it how? These are just details. As with any good "space mining" scheme these things will be worked out later.
Engineering is one skill set, visionary thinking is completely different. :-)
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