Bulldrek v3.0

So I was watching Deep Impact tonight (good movie, and more realistic than Armageddon, IMHO) and I got thinking about explosions.

One of the things that make explosions so damaging is overpressure of atmosphere. So let's say you detonate a sizable nuclear weapon in the atmosphere and you can potentially get catastrophic results. However, if you detonate in space, wouldn't there be far less yield from the same size weapon? There would still be a sizable release of energy (mostly heat), but how much would that affect a nearby vessel or astronomical body?

Say your safe distance from ground zero on earth was 10 miles. What would the "ground" zero be in a large vacuum (i.e. space)?

UncleJoseph wrote:However, if you detonate in space, wouldn't there be far less yield from the same size weapon? There would still be a sizable release of energy (mostly heat), but how much would that affect a nearby vessel or astronomical body?

The primary blast damage would be extremely minimal, as the only medium for the blast effect to propagate through would be the material of the bomb itself, which is relatively minimal.

The heat and light from the bomb will dissipate at the inverse cube of the distance [like any spherical waveform], and anything capable of surviving in space should be able to shrug off even relatively close detonations.

The primary danger is radiation, which won't be attenuated by atmosphere. Though orbital vessels should have significant radiation shielding, a nuclear blast still lets off quite a lot of hard radiation.

Conveniently, here's an image showing the relation of intensity depending on altitude, from everyone's favorite NASA page, "17. NUCLEAR WEAPON EFFECTS IN SPACE."

Would the EMP blast take out satellites?

Depends on how close they are, but the safe radius for satellites is going to increase, too [over the safe radius of atmosphere detonation as it relates to satellites]. Worse, if the blast is in orbit, it'll excite the Van Allen belt, and end up killing most sats that way.