Deep Space
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I think it's time for an experiment! Take a long handled 1" and 1/4" combo wrench from each of the major manufacturers including the big Chinese forging companies and retrograde them in and see what lands!
MAKG1
Touchdown! Greaser!
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Not that it matters all that much (qualifications don't mean what people think they do), but I've been a NASA engineer since the summer of 2000.
If the wrench entered the atmosphere, not much of it would make it to the ground. But it won't make it there until the ISS does. You just can't throw that hard.
People don't understand orbits very well in general. The art of orbiting (with apologies to Douglas Adams) is, very literally, to throw yourself at the ground and miss. You fall toward the ground just like you would any other way, but you're moving so fast horizontally that you miss the planet on your way down. Thinking about it that way, do you think you could make much difference with your throwing arm? Only if you can throw to orbit....
Keep in mind that the atmosphere is very thin compared to the size of the planet. It's not a bad approximation for orbital mechanics to pretend it isn't there. The ISS orbits at around 250 miles altitude. How far can you throw? I'd suspect the answer might get you to 249.9 miles (that's an almost-200-yard throw!), but not a whole lot further.
What if you throw it out and backwards?
John Baker
Final Approach
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John Baker
Captain
Final Approach
What you just posted I actually knew. I do not, however, know the mathematical equations behind it all though.
As far as learning goes I would point anyone interested who happens to own an iPad or has itunes installed on their Mac or PC to look into 'itunes U'. They have a gazzilion online courses on all this sort of stuff.
MIT has an entire section called MITopencourseware (OCW). Physics I: Classical Mechanics is a great place to start and goes over all the stuff covered on this thread. I have to admit that I get buried pretty quick in the formulas presented there.
iTunes U is a wonderful ressource for anyone interested in learning just about anything...and it's free.
You can also get Angry Birds Space...
olasek
Pattern Altitude
Hmmm.. unless I misunderstand it, I don't see it that way. ISS receives occasional boosts to keep it in orbit, a floating wrench would be left to its own devices. But orbit decay is dictated primarily by the object relative density, a wrench is probably a bit denser than the whole station so indeed in direct competition with the free floating ISS it could stay up longer. So whether such floating wrench would come down before the station does is open to debate since we have a few counterbalancing factors, who knows how long they will decide to use the ISS.
comanchepilot
En-Route
You need to add 11,000fps to the velocity for it to escape the Earth's gravity well . ..
Now - if you threw it behind you, and would need to decelerate it by about 300fps in order to slow it down enough to immediately de-orbit- yes - they only slowed the Space Shuttle down by 200mph to bring it immediately back to Earth.
If you could throw it 60mph - prob the max given the inflation of the suit - it would take perhaps a week or two to encounter sufficient drag to be dragged back into the atmosphere -
Throwing the wrench AT the Earth speeds it up - which would actually RAISE the orbit of the object - throwing it away from you would have the opposite effect but the orbit would simply become more elongated - and not change - you need to throw the wrench either into the orbital plane or away from it in order to truly effect the orbit. Throwing it perpendicular to the orbit would shift the plane of the orbit . . .
But remember- ANYYHING you do is subject to Newtonian physics - if you throw the wrench you will impart an identical shift in the orbit of the ISS. While the mass of the station is much much larger than the wrench whatever you do will affect the orbit of the station no matter how slight.
Now - if you threw it behind you, and would need to decelerate it by about 300fps in order to slow it down enough to immediately de-orbit- yes - they only slowed the Space Shuttle down by 200mph to bring it immediately back to Earth.
If you could throw it 60mph - prob the max given the inflation of the suit - it would take perhaps a week or two to encounter sufficient drag to be dragged back into the atmosphere -
Throwing the wrench AT the Earth speeds it up - which would actually RAISE the orbit of the object - throwing it away from you would have the opposite effect but the orbit would simply become more elongated - and not change - you need to throw the wrench either into the orbital plane or away from it in order to truly effect the orbit. Throwing it perpendicular to the orbit would shift the plane of the orbit . . .
But remember- ANYYHING you do is subject to Newtonian physics - if you throw the wrench you will impart an identical shift in the orbit of the ISS. While the mass of the station is much much larger than the wrench whatever you do will affect the orbit of the station no matter how slight.
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airguy
Cleared for Takeoff
To throw something such that it would re-enter the earths atmosphere, you only have to change the orbit such that the perigee is low enough that significant atmospheric drag takes over and reduces the tangential velocity below the point at which it can climb back out towards apogee, and at that point you're going in. For low-earth orbit you don't need much delta-V to get the lowest point of the orbit down to atmospheric interface - the recent Dragon space capsule flight by SpaceX only needed 100 meters/sec delta-V retrograde after separating from ISS to drop the perigee into interface for re-entry.
As Comanche-Pilot mentioned, if you don't get it low enough so that it re-enters on the next orbit, the slightly increased atmospheric drag at perigee will continue to sap energy orbit after orbit until drag wins.
So the issue becomes - can you throw something backwards from your current orbit at 100 meters per second? (That's 223.6 mph)... How good is that pitching arm?
As Comanche-Pilot mentioned, if you don't get it low enough so that it re-enters on the next orbit, the slightly increased atmospheric drag at perigee will continue to sap energy orbit after orbit until drag wins.
So the issue becomes - can you throw something backwards from your current orbit at 100 meters per second? (That's 223.6 mph)... How good is that pitching arm?
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What happens when you add an outward trajectory to rearward?
MAKG1
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Any impulse applied to the station upon throwing will be returned after completing one orbit, when the thrown object collides with the station.
It's not all that significant, anyway. You would get much more from ejecting a Progress.