Wednesday, June 15, 2005

Let's break it down
InstaPundit quotes this piece about the militarization of space:

So scary tales about U.S. 'death stars' hovering over target countries promising swift strikes from space rely merely on readers not understanding the basics of orbital motion in space. A satellite circles Earth in an ever-shifting path that passes near any particular target only a few times every 24 hours, not every 10 minutes. It's quicker and cheaper to strike ground targets with missiles launched from the ground.
This may be true, but there are a few problems as well. For one thing, if the US built a Death Star, we wouldn't need it to be "near" a target—a death star is a doomsday device designed to destroy planets, not to carry out out tactical strikes on their surfaces.

Next, the author says that a satellite only passes near a particular target "a few times every 24 hours, not every ten minutes." Well, let's think about this. Assume that "a few" means twice a day (I don't know the real number, but I'm trying to be conservative in my assumption). This means it takes a satellite 720 minutes to travel around the planet. Now, we can assume that a satellite is not in range for an instantaneous moment, right? Let's say it's in range for fifteen minutes (I believe it's more like a half an hour, but again we'll be conservative). There are 48 fifteen minute segments in any 720 minute (12 hour) period. Which means, if we built 48 weaponized satellites, we could have any given target area on the face of the planet covered 24 hours a day.

Doesn't seem quite as far-fetched as the author aims to make it, does it? If I'm right and the target-range period is more like thirty minutes, we'd only need 24 of them. You get the point—the exact thing that this author is trying to make sound completely impossible is, in fact, very possible.

And there's more! Go anywhere on the planet right now, and bring a portable GPS receiver with you. Turn it on. Go to your connection status page. You will see that you are in range of at least 5, and my guess would be more like 7, GPS satellites. Anywhere on the planet you are ALREADY in range of a military satellite. Now, granted, these are not weaponized. But the Pentagon has already undertaken to built a satellite network that covers every spot on the planet with extreme redundancy—why is it so hard to believe that they might do the same thing again and slap a weapon on it?

1 comment:

Dave Justus said...

I think we are a long way away from feasible space based ground attack satellites. We can fairly quickly hit everywhere we want to know without them, there is not military necessity that justifies the increased expense of this sort of platform (and it would be far more expensive.)

There was, during the cold war, good reason to have a nuclear armed satellites to act as a deterent. Unless the enemy had a-sat capabilities, they would be unable to prevent a retaliatory strike. The same justification for our nuclear submarine fleet. To the best of my knowledge though, neither side deployed these weapons during the cold war.

Militarizing space is important now however. As you noted, we rely heavily on our GPS system, and that means we must be able to defend that system, and we also want to be able to take out similar systems that are under the enemies control. This is most efficiently done with space-based assets.