It came from outer space!

Hi, Roamy here.  The Leonid meteor shower is tonight, so after moonset and before sunrise, look up.

This has been predicted to be a fairly light shower with 20 meteors an hour or so.  Meteors can damage satellites in orbit, but the satellite operators can take steps to minimize impacts, and the meteors themselves are small.  A far greater concern is manmade debris orbiting the Earth.

You want to fly through THAT?!?! (click to embiggen)

That’s an old map of what U.S. Space Command tracks in orbit.  Dead satellites, old rocket stages, dropped tools, all flying at kilometers per second.  They can’t track the small stuff – the paint flakes, the bolt floating free, the shrapnel from previous impacts.

When I say old, I mean that I saw that graphic before the Chinese anti-satellite test and the collision of two other satellites.  Fengyun-1C is responsible for 18% of the space debris currently in low Earth orbit.  (source:  We also seem to be stuck in a deep solar minimum, and while that’s good for some things, it means that the Sun is not heating up Earth’s atmosphere as much, and there’s not enough drag to make these pieces of space junk fall into an ocean somewhere.

What does this mean for you on the ground?  Think about your GPS satellites flying through that, and all the equipment that relies on those GPS satellites to work correctly.  You can manuever away from possible collisions, but that takes fuel, and there’s no refueling in space, yet.  We are vulnerable, which is why there’s a push for better shields (which is still fodder for the next post).

In the meantime, stars fell on Alabama.

XBradTC sez: Think for a moment about just how critical GPS is to our military operations today. Most of the bombs dropped in action have GPS guidance. Virtually all of the command and control systems our troops use have embedded GPS systems. Without GPS, commanders and troops will have a much, much harder time keeping track of where friendly forces are. And then there’s communications. Much of the communications systems worldwide rely on the precision timekeeping of GPS systems to stay in synch. Loss of GPS capability would be a disaster.

3 thoughts on “It came from outer space!”

  1. I think the relative size of those white dots make the sky look more crowded. It a REALLY big area up there with a relatively low percentage of the area taken by objects.

    Also, GPS is a redundant system with many satellites working to make your GPS receiver work, so I don’t see how a collision or two would take the system down.

  2. Sure, the big sky theory works, to a great extent. But when it fails, it’s rather spectacular. Roamy has a picture of what a paint chip did the the windscreen of a shuttle. I’ll nudge her to post that.

    And yes, there is a great deal of redundancy built into the GPS constellation. My point was more about the vulnerability of our forces to a single point of failure. What if a solar flare or other event compromises the system?

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