"Earth like"? Earth's atmosphere changed in the past and habitable planets/satellites aren't al supposed to be Earth-like. We're discussing planetary bombardments in general...the list of targets include planets/satellites that have been colonized, not Terra-Vasuda Prime(home planets). Try to imagine something like the Moon with a very poor atmosphere...I don't think the Harbinger would be that lethal there.
I'll just give my list again here from my previous post since i was imagining an explosion in varying atmospheric and no atmospheric conditions
1. a nuke going off in space is just an unleashing of energy, in space you'd probably want focussed charge nukes to be able to do any damage to the heavily armored capships in fs.
2. an atmosphere provides a medium for some nasty shockwaves. Different atmospheres will have different results in the severity of the shockwave. I'm guessing the severity of the shockwave would be judged by atmospheric density and pressure (based on how thick the atmosphere in question is and whether or not that'll be a bigger or smaller shockwave). One thing is sure of all nukes going off in atmosphere. Atmospheres will provide that medium for a shockwave where a vacuum wont provide a medium for such a nasty shockwave.
OK, with that being said a second time, plus the fact that not anyone in this topic was getting into the specifics of atmospheres either in this whole thread. So when anyone talks about atmosphere in here, they're probably talking about something like vasuda primes atmosphere which was very much like earths (considering that humans could survive in their atmosphere which happens in the fs1 ref bible). How do i figure in this topic that everyone was talking about an atmosphere similar to earths? Everyone in the topic was basing off of information known about our own local atmosphere which i assume was happening since no one got into specifics. The only person who got into specifics about this was you mobius, and you don't read minds. It's not a bad turn in subject at all. In fact it's quite a necessary one when talking about orbital bombardment. But the fact remains, no matter what kind of atmosphere there is, a nuke going off inside of it will have a lot bigger shockwave than the a nuke going off in space. And since you didn't want to be wrong you brought in the "well well what about other kinds of atmosphere?".
This led you to the moon. LOL, i mean talk about an obvious ploy here...desperation, perspiration. The moon is a horrible thing to compare with a real atmosphere. The moons atmosphere is so negligible it might as well be just a nuke going off in a vacuum. Now if you want to say like a nuke going off on mars as opposed to earth, then that wouldn't be a ploy, that would actually further the argument. As such, Mars will probably result in a smaller shockwave because mars's atmosphere is a lot thinner.