A sibling comment of mine references https://www.adrc.iastate.edu/files/2012/09/IAC-09.C1.3.1.pdf https://www.adrc.iastate.edu/files/2012/09/IAC-09.C1.3.1.pdf

A sibling comment of mine references https://www.adrc.iastate.edu/files/2012/09/IAC-09.C1.3.1.pdf https://www.adrc.iastate.edu/files/2012/09/IAC-09.C1.3.1.pdf Section 6.1 is on nuclear stand off explosions. > The nuclear standoff explosions require an optimal standoff distance for a maximum velocity change of a target as- teroid. Therefore, we have to determine how close the nuclear explosion must be to effectively change the or- bital trajectories of asteroids of different types, sizes, and shapes. The precise outcome of a NEO deflection at- tempt using a nuclear standoff explosion is dependent on myriad variables. Shape and composition of the tar- get NEO are critical factors. Section 6.2 is on kinetic impacters... > A somewhat futuristic, solar sailing mission concept utilizing a 160-m solar sail to deliver a 150-kg kinetic impactor into a heliocentric retrograde orbit was studied in [25-28]. Such kinetic impactors will result in a head- on collision with a target asteroid at its perihelion (as illustrated in Fig. 1), thus increasing its impact velocity to at least 70 km/s. The NEAR Shoemaker study of as- teroid Mathilde and the Japanese Hayabusa mission for exploring the asteroid Itokawa suggest that many aster- oids are essentially “rubble piles.” Consequently, a practical concern of any impulsive approaches employing kinetic impactors or nuclear explosions is the risk that such high-energy deflection attempts could result in the frag- mentation of NEOs, which could substantially increase the damage upon Earth impact. And then, section 6.3 is a fun one: Gravitational Binding Energy > the disruption energy per unit asteroid mass is predicted to be 150 J/kg for strength-dominated asteroids. This indicates that a strength-dominated, 200-m asteroid would not be disrupted by a 150-kg impactor at a high impact velocity of 70 km/s. Also in Ref. 5 (pp. 135-136), the energy (per unit asteroid mass) required for both disruption and dispersion of a 1-km asteroid is predicted to be 5 kJ/kg. Thus, the feasibility of the most kinetic-impact approaches for either disrupting or deflecting an incoming NEO depends on its size and composition (e.g., solid body, porous rubble pile, etc.), as well as the time available to change its orbit. These are from 2012, and we've had a decade more experience (and a mission to try it out) since then... but it's interesting to look at and the math in the paper doesn't change.