Now, I'm just making a SWAG here, but generally the power supplies for these things aren't much more than slivers of material for generalized heat. Most of the power is solar since there's generally plenty of that up there (the longer range satellites we send to other planets need a stronger core to compensate for the diminished light).

If I had to guess (and, well, I do) I'd say plutonium, but I'd also guess a very, very small amount. So small that if it burns up on reentry, no big deal and if it doesn't, well still no big deal. I'm sure they'll push it into the ocean and while I cannot confirm nor deny this, that's pretty much where nuclear waste from our subs goes anyway.

I absolutely have no fear of the fuel atomizing perfectly and killing the entire planet.

It's very unlikely (not absolutely impossible, but very unlikely) that this thing has a reactor. Most likely it has a thermal Plutonium power source (Plutonium is warmed by its radioactive decays). Plutonium is indeed radioactive, but it's not nearly as evil as fission products. It's more toxic as a heavy metal than it is as a radiation source.

It's really not an issue.

Solar would give more power cheaper in orbit, so plutonium is probably right.

I doubt that this satellite is powered by a nuclear reactor. The spacecraft that use plutonium are for deep space where the solar radiation is too weak to power it. The hazardous element is probably beryllium. It's a strong, stiff, and light metal, ideal for satellite structural components. The downside is that it can cause deadly allergic reactions cancer, primarily through inhalation of small particles - the same sort of particles you'd expect to detect in the air when a piece of beryllium is partially consumed during reentry.

I think that the real problem is that it is one big mass and some of it is likely make it to the surface without burning up.

Target practice for the anti-missle system that has been (sort of) deployed?

Or we could invite the Chinese to blow it up. They seem to enjoy it.

Or, we could send Joe up with a mess of Boomerite. B-)

I guess it would have been too much trouble to go and either refuel the bird's rockets, or at least remove the fissionable material?

With what for spaceships? We're not building any more Space Trucks and the ones we've got are old and fragile.

OK, it was my understanding that the power levels 'sometimes' used in some satellites left no choice but to have a reactor on board. Anything that uses active radar for example. There are different kinds of spying. Then there is the need to be active while in darkness, and yeah, I know-- batteries. But if you're 'running power' (radar) you need more kick, plus the battery systems, at least until fairly recently, were the service-life limiting factor on many a satellite (motor fuel on others) and when you're the .gov you don't play by the same rules.

We played with beryllium a little bit (believe it or not) in musical instruments. One trumpet maker, Schilke, used a beryllium-bronze alloy in some of their more exotic models. We'd solder, sand and buff the stuff, but I don't recall ever dying from it.

I'm just wondering aloud is all. Sure, our government exploded literally tons of U235 and plutonium over our own soil back in the days of above-ground bomb tests. Most of us survived OK, and anything on a satellite will be tiny by comparison.

Now imagine the media reaction if this bird were privately owned, packing the same materials.

Pu-239 used as a heat source for a thermo-couple power generator. The concern for Be is very small. Yes it can be toxic (all powdered metal is not really good for you) but the people that have had problems with it are those from the early to mid nuke bomb making that were machining the hell out of Be. But the exposure that you would get from the Be it (if was made entirely of Be) would be insignificant compared to what you would receive from your airbag going off.

Sam is right in that you would be more concerned with the toxicity of Pu-238 or Pu-239 than from radioactive decay. If this came down in the eighties or before they would not have told you anything. But now because of PSH they have to tell you if someone farted in space because there is an off chance that you might smell it.

They wrote off that satellite right after launching it as it would not respond to commands or even answer comm requests, or so they said. So no point in refueling it.