Something just does't stack up right
November 25, 2008 8:24am CST
If you have watched the national news lately you have probably heard about the $100.000 tool pouch that was lost off the space station. The said yesterday the tool pouch would fall to earth and burn up before it gets to earth. This just doesn't sound right to me. My question is this: If that tool pouch will fall to earth that why soes the space station not also fall to earth? They were both at the same location when the pouch was lost. If you figure this one out then let me know.
1 person likes this
• United Kingdom
25 Nov 08
I heard about that story and I also saw the news clip where it slowly started drifting away from the astronaut! You have definitely come up with quite a puzzle though! I'm sure they may have made a mistake by saying what they said! As far as my limited knowledge goes in terms of space, the space station is stuck in the Earth's orbit and remains in the same position. However, the tool bag that was lost, this had some velocity to it, i.e. it was slightly moving, it wasn't stationary like the space station. So, I guess there would be a danger that it could drift out of the Earth's orbit and suddenly be pulled in by the gravitational pull of the Earth! We think that the space station is moving but it isn't. It's the Earth that's spinning! Anyway, I hope that there's some logic to what I have just said as I'm starting to get confused now! Andrew
• United States
14 Dec 08
The space station is definitely NOT stationary. Technically, it and all other objects in orbit are constantly falling towards the Earth; the station is moving faster than the minimum orbital velocity but slower than the minimum escape velocity. Yes, the Earth is spinning, but the station is still moving above us (here is a visual: For simplicity's sake, assume that the stars are stationary in the short run. If the ISS were stationary, it would appear to move in the same manner as the stars. BUT if you actually see the station go overhead it moves quite quickly across the sky in a matter of minutes rather than hours). As for the tool bag, it was moving in about the same orbit as the space station (approximately the same velocity and direction), but its lower mass means it is more susceptible to changes in velocity. I believe someone mentioned the drag of the atmosphere; this drag would be enough to slow the bag beneath the minimum orbital velocity, and the bag would fall to earth and burn in the atmosphere.
28 Nov 08
It's perfectly simple. Both the International Space Station and the tool bag are in low orbit (approximately 200 miles above sea level, give or take). High enough to be outside the sensible atmosphere, but still low enough for there to be a tiny amount of air drag. In the normal course of events, both objects would be slowed down enough by this microscopic amount of air drag to lose orbital velocity and re-enter the Earth's atmosphere within a few years. This will indeed happen to the bag, but the space station is periodically boosted up to a higher orbit to compensate. To be in a permanent orbit, like the Moon, they would have to be a lot further out.