Viewing a single comment thread. View all comments

UHF1211 t1_j6eb2r4 wrote

Reply to comment by SavageRat in Asteroids sudden flyby shows blind spot in planetary threat detection by coinfanking

Wouldn’t work, there is no air in space. Something would have to be attached to the asteroid or hit it in order to nudge it a bit.

−8

HIMP_Dahak_172291 t1_j6erdci wrote

Close nuclear detonations would still push the asteroid simply by differential heating and vaporizing the rock on the facing side. Not much of a push, but it is one. Nukes might be the only recourse for rubble asteroids too. You'd have to have the warhead on a robot that would push itself inside before detonating for it to do any good, but I can't think of a better option.

5

Sumwan_In_Particular t1_j6hes89 wrote

That’s an interesting idea about the robot. I’m wondering what others think about using:

https://en.m.wikipedia.org/wiki/Bunker_buster

There’s a section for nuclear, an adaptation of which, might be a realistic approach delivering a nuke deeper into an asteroid. Or a train of them, hitting the same point.

Edit: I love that you mentioned rubble asteroids btw, bc we might have a better chance at rendering those (relatively) safe. I’d be most concerned if the asteroid was a large chunk of iron perhaps. I doubt the bunker buster would have nearly the intended effect.

1

HIMP_Dahak_172291 t1_j6hpgfi wrote

From what I have read the rubble asteroids are the hardest to do something about. We can redirect a lump of iron provided we have enough warning, but rubble asteroids are much trickier since you cant just push them out of the way. The only two options are gravity tractor or demolition. Neither option is easy and both require lots more advanced warning compared to a similar mass solid asteroid.

Bunker busters wouldnt be particularly useful since the warhead wouldnt survive the impact at the speeds necessary to get sufficient penetration on a rubble asteroid big enough to need redirection. The drone idea is harder, but if you can get several deep enough with big enough bombs the blast should at least nudge the thing off course.

2

UHF1211 t1_j6ev1uu wrote

This is true if close enough and it would need to be pretty close, space is big and that heat would dissipate rather quickly otherwise but still perhaps just enough to push it ever so slightly out of the way.

−1

HIMP_Dahak_172291 t1_j6evwqh wrote

Yeah, it would have to be very close. The energy dissipates exponentially with distance. The more surface area exposed to the blast the asteroid has the more energy would be transferred though, so for really big ones it might be more effective than the basic chemical thrusters we have now. Not saying alot of course. A dinosaur killer has enough mass its debatable if we currently have the tech to deflect one that would hit within a decade or two.

2

SavageRat t1_j6h7shv wrote

My understanding is that the steam released from the flash boiling of water vapour in the rock would be enough to push an asteroid off course enough. As long as it was sufficiently far away.

1

UHF1211 t1_j6ha6u7 wrote

How do we know there would be water on an asteroid headed for earth? Not all installer objects have liquids on them. How long would it take to deduce this and would this time be better spent trying other ways of deflecting it?

0

SavageRat t1_j6hhxzg wrote

Unless it's was a solid metal of some kind, I believe it is a given that any rock based asteroid would have some level of moisture/ice in it.

2