NASA designs "Armageddon" spacecraft

[j05h]

<i>>The problem is that this is a bad idea with loosely structured bodies like rubble piles and comets. You also have to do it years or decades before impact.</i><br /><br />The funny thing about the "nuke it till it stops moving" concept is that there are simply better ways to do it. The only situation that nuclear charges make sense is on something with a few weeks or months notice, and even then it is no guarantee of success - and with a rubble-pile asteroid, nuking it is a guarantee of wider damage. Mountain or smaller hill, broken up and coming in at 35km/s it isn't going to burn up much in the atmosphere. Instead of one "Chixulub" this would cause hundreds of "Tunguska" events. <br /><br />The "gravity tug" is predictable, technically feasible and protest-free. Another option is changing the asteroid's albedo using paint or plastic film. Burning parts of the asteroid using solar reflectors can be effective and doesn't cause protests. <br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[holmec]

<blockquote><font class="small">In reply to:</font><hr /><p>The funny thing about the "nuke it till it stops moving" concept is that there are simply better ways to do it.<p><hr /></p></p></blockquote><br /><br />I doubt that's what their going to do with the nukes. The thing is nukes provide quick and large amounts of energy to nudge the asteroid and guide it. If you nuke it till it stops, then it falls directly into the Sun. If you nuke it to destroy it, it reassembles. <br /><br />If your talking about options. You could attach a huge solar sail to it. The good thing about the solar sail over the tug is than much less propellant is needed <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[comga]

Please don't be so literal. "Nuke it till it stops" does not mean canceling out all of its momentum. It is, however, good shorthand for a proposal to hit a target with up to six 1 MT nuclear warheads.<br /><br />Solar sails are nowhere near TRL9. No one has successfully put up a big one, and there are enormous issues. You can't attach much to asteroids, which are probably spinning, perhaps chaotically, and structurally unsound.<br /><br />Read Melosh's discussion earlier in the thread. (Jay, by the way, is an expert on cratering, and even he favors a gentle approach.) Read Clark Chapman's rebuttal to the NASA study. Check out the B612 organization web site. <br /><br />As said earlier, nukes might be a last resort if we only had months or weeks, but Apophis isn't a danger until 2036. On top of that, we have the Earth swing-by in 2029 to use as a lever to toss it out of our way.

 

[publiusr]

It is not "an excuse" for Ares V--the future of man in space. It is a valid use. Durda's 'gentle' approach is what is suspect. We had a Delta II payload ram a comet after all with minimal impact--or none at all--to the trajectory.<br /><br />You had better have a sizable payload--esp if you want something besides an empty centaur stage out there with no fuel to push with.<br /><br />Durda's apprach may not even work.<br /><br />I'll take a big rocket stage with plenty of fuel for the gravity tractor to even have a chance at working.