Quote:
Originally Posted by Ian Robinson
Straight from Hollywood.
So , considering we can't even get astronauts even out of low earth orbit now , and have only managed to get robots not much bigger than a kid's tricycle onto another planet in recent years and most of these have - missed the target planet , or crashed and burned , or simply failed and sailed past the target PLANETS on into infinity , how will we get a drilling rig and astronauts (cant trust a robotised rig in critical mission like this that the survival of humanity might depend on) safely to the asteroid's surface perhaps several million or even hundreds of millions of km from earth (depending on its orbit and velocity) ?
just how is that feat going to be achieved ?
not to mention getting any sort of substantial drilling rig and the astronauts safely onto an asteroid's surface ? and then there is the problem of working at drilling boreholes in the surface of the asteriod deep and broad enough to plant enough thermonuclear mines of sufficient power to make any difference when the nukes are detinated (not talking little firecrackers of a few MT yield here - probably need nukes with yields in GT yield class to even dent dangerous asteriods , and all this under zero or microgravity ?
And who are we going to trust to develop such powerful nukes - and where will they be tested ?
Brute force is not the answer and is unlikely to work.
The most promising proposals I have heard are to harpoon the asteriod on flyby of a space craft and thereby attach a humungous solar sail to it, and to sail it slightly off trajectory over several years , or to set up a humungous rail gun , or several of them on the moon's surface and fire large very high kinetic energy (ultra high velocity) projectiles at the asteriod , mining the raw materials on the moons surface and making them insitu , and firing them at the asteriod at velocities that are very high , in order to impart enough kinetic energy to change the asteriod's velocity enough for it's orbit change slightly though enough to miss the earth.
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Your objections are to a strawman and your alternative is fanciful. Missiles that hit things, burying themselves a few meters then blow-up are a well developed terrestrial technology that could easily be adapted for use in space. Missiles are generally unmanned. A nuclear explosion occurring meters below the surface of an asteroid would (conservatively) send thousands of tons of rock moving away from it at hundreds of meters per second. This would change the orbit of the asteroid as a consequence of Newton's laws of motion. I don't know of any other way to impart such a large impulse to an asteroid in a sub-decadal period.
The alternatives you suggest depend on unproven technologies, would have large lead times, or would be enormously more expensive. It's ironic that you object to nuking an asteroid on the grounds that "we can't even get astronauts even out of low earth orbit now" then propose as an alternative that we "set up a humungous rail gun... on the moon's surface and fire large ... projectiles at the asteriod , mining the raw materials on the moons surface and making them insitu".