Your math actually doesn't add up. You would have to account how much energy it takes to disintegrate 1 kilo of biological mass of a [b][u]single species [/u][/b] there can be alien body mass that could be more resilient than human flesh. Also, take into account that when the halos fire, it sends out a [i]pulse [/i] in all directions into the [b][i][u]vacuum of space[/u][/i][/b] since most of the universe is vacuum, around 99.99999--% is vacuum and so on. 0.0000000-1% (again very small) hits actual body mass, let alone a planet IF it has biological life. Most of the energy is wasted in space. All you stated was how much body mass was destroyed. Even then, was the pulse through space just enough to break down biological mass(bare minimum) or did the energy they put in on average for each lifeform was the energy equivalent of using a nuke to microwave a burrito. (Example, it would take 10 joules of energy to disintegrate one lifeform , but to the forerunners used a pulse, on average, had 100 joules of energy, just to be safe. Your math was a valiant effort, though. [spoiler]The numbers I gave aren't accurate, but it's safe to say that the ratio of vacuum of space to celestial body mass is similar to what it actually is [/spoiler]