
How to Deflect an Asteroid - happy-go-lucky
https://news.mit.edu/2020/how-deflect-asteroid-mission-0219
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aurizon
The asteroid trajectory must be refined - as per MIT. Based on this data, the
structural integrity must be assessed. I expect asteroids to vary from rigid
iron rich and tough bodies that are amenable to a 'point thrust'. By that I
mean send a rocket with one or more rocket motors and fuel with separate fuel
supplies that are anchored to a point, and fired to transfer momentum to the
asteroid as calculated. If it rotates - what rate? Assess, and fire only when
properly placed. Any rotation would be known and the thrust point optimized
for the task. This installation would be re-supplied with fuel and oxidizer on
a recurring basis. The whole thing may be manned or robotic if capable. If the
asteroid is a gravitational aggregate of gravel, sand, and smaller asteroids -
this will not be amenable to a point thrust - it would scatter apart as the
inherent gravity would not keep them all together. In that case, a central
detonation chosen to direct the path away would be detonated. This would
scatter the debris in all directions. The scatter would be observed and the
larger bits capable of entrym to the surface tracked. The gravel can be
ignored. Larger bits assessed on a case by case basis and tracked, and
detonated if possible. One hopes the recent project to assess all near earth
objects that might intersect will give 5-10 years of advance warning so that
measures can be implemented.

Some people have suggested a 'gravitational tug' \- mass placed near the body
to attract it. This is a dumbass foolish suggestion, since gravity is the
weakest force, and and object capable of the task would be in the same orbit
as the asteroid and of similar weight (in order to atttract with a meaningful
force) - this means it would be a similar threat. Time is what we need. With
10 years warning we can assuredly move a 10 KM asteroid onto a safe path for
the initial impact and then progressively move it towards entry into the sun -
the safe end point.

The decision as to nuclear detonation, chemical detonation and persistent
thrust application would be decided on the merits. Persistent thrust is by far
the most efficient method.

