In atmosphere, this energy most immediately goes to the surrounding air which produces the characteristic shockwave most are familiar with. It's not true that the shockwave decays as 1/r3 as the superheated atmosphere still gets pushed out with the blast and that energy will be transferred to a target, although the actual nature of the damage may vary substantially due to the lower per-particle energies involved. Thus 1/r2 is the right first approximation.
Well, I must agree that 1/r^3 is too simplistic - it's about air ball heating, not shockwave: in the air (0-5000m) shockwave is about 1/3 of nuke's energy, while 1/6 to 1/5 is heated air ball (that is around 1/r^3 decay).
Another 1/3 is UV to IR reemission, that will not produce momentary inner damage, though it can overheat the ship.
Speaking of small light life-pods - I'd say they have small chances to withstand nuke closer than several kms, and in 5 sec they have no chance to go this far
in normal space.
Though, on the other hand, Aurora Lore is telling us that these velocities are effectively projective, so it's not clear what Aether's velocity it will represent.
To avoid these questions, I'm supplementing Aurora Lore for myself with a notion, that guns and emergency catapults are just transferring their pods and impacts through Aether, not through normal space, so it's like small hyper-jumps, and they are obviously able to open it in any direction even through the planet body (though haven't enough precision to target inside another hull). So, it's quite convenient, that life-pods are jumping outside of the ship at the distances up to 10 000 km nearly instantly, and so they are quite safe from explosions, that destroyed their ship.