Deflecting Asteroids with Paint

schnippy writes: "Researchers at the University of Arizona have calculated that small earth-crossing asteroids can be deflected by "coating them with a layer of white paint or dust." This finding won't be of much help against the larger doomsday asteroids (like the recently discovered 1950 DA) but it will help deflate military proposals to use nuclear weapons to deflect potentially hazardous asteroids."

Comments

What a poor writeup

[Anonymous Coward]

Most articles on the 1950 DA asteroid mention that it can be deflected "by selectively dropping white chalk or black carbon powder to darken or lighten some regions". That's because the potential impact is in 878 years, so a small nudge now can make a huge change over many centuries. In other words: yes this paint technique can help against 1950 DA. Claiming anything else shows a poor understanding of the basics of asteroid deflection.

Chaos Intervenes

[Perdo]

If predicting the trajectory of an asteroid's orbit is so heavily dependent on surface reflectivity, how do we know the change we make will not bring it closer to earth and not farther away? I liken it to our ability to change the weather, but not predict the weather.

I would prefer to make the trajectory change closer to the impact event so that we could more accurately predict the results.

Re: One (slightly used) asteroid

[Raetsel]

• "...zero G raw materials for future missions."

Or... a counterweight for a space elevator!

I suppose the longer we wait, the more stuff we can take -- it'll take less fuel to get there. (Unless we're using antimatter propulsion in 850 years or so... then I guess it really wouldn't matter.)

Re:Use a Laser

[Tablizer]

(* Why not use a laser to heat the surface of the asteroid, his will create a hot plasma jet which
will alter the trajectory of the asteroid. *)

The energy/force exerted it not likely to be any more than the power going to the laser itself. (You know, laws of conservation of mass/energy, etc.) Our lasers currently are way too weak for such.

We have a hard enough time using them to blow up missles, and those lasers can only peak for a few seconds before they melt.