# Redirecting asteroids on an impact course by momentum transfer **URL:** \ **Category:** Factual Questions\ **Created:** [December 17, 2017, 4:53pm UTC](https://boards.straightdope.com/t/redirecting-asteroids-on-an-impact-course-by-momentum-transfer/804718 "2017-12-17T16:53:54Z")\ **Posts on this page:** 1\ **Showing post:** 21
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [December 18, 2017, 2:32am UTC](https://boards.straightdope.com/t/redirecting-asteroids-on-an-impact-course-by-momentum-transfer/804718/21 "2017-12-18T02:32:35Z")
> [@Dr.Strangelove](#): > > Sure it did–a little bit. If the truck was traveling through a vacuum at 60 mph, and there was going to be another truck 3000 miles away precisely 50 hours from now, that bird would have prevented a collision. Sorry if you didn’t get my point, which I admit I made obliquely. My point was one of scale, the same problem with scale that made SamuelA mischaracterize Stranger’s point. Here’s the full post from the other thread. > [@The K-T Asteroid: Would Modern Instrumentation Have Seen It Coming?](https://boards.straightdope.com/t/the-k-t-asteroid-would-modern-instrumentation-have-seen-it-coming/804670/7): > > As it happens, I’ve worked on a study of this very issue, and proposed a concept for redirecting objects of moderate size (~1 km diameter iron-nickel bolide). In [POST=12775897]this post[/POST] I addressed the feasibility of shifting the trajectory of an incoming hazardous object. Redirecting an object of such size is at least remotely feasible, provided you can deliver several dozen devices to intercept with the object, which is more of a logistical challenge than a technical one. Redirecting a much larger object, however, becomes a substantial challenge not only because of the additional mass but because the impulse will impinge upon only by a fraction of aspect of the body and would likely be absorbed as deformation within the body (inelastic transfer or liquification) rather than uniformly delivered to the entire aspect. Moving really large masses requires some fundamentally different method of propulsion than just pushing because at those scales a “solid” body doesn’t act very solid. > > Stranger He is specifically referring to an extreme example of much larger than 1 km, on the order of 10 km, like the K-T asteroid. On that scale a single nuke trying to affect the asteroid has about as much chance as the bird affecting the truck. SamuelA is just wrong in his scenario and his criticism. Stranger is correct that a different strategy must be found. --- _[View the full topic](https://boards.straightdope.com/t/redirecting-asteroids-on-an-impact-course-by-momentum-transfer/804718)._