Astronaut Loses Tools While Performing an EVA 445
tpheiska writes "NASA press release states that 'At approx. 3:33 p.m. EST, Piper reported that one of the Braycote lubrication guns had released grease into her toolbag. As she was cleaning the bag and wiping the tools and equipment inside, the bag floated away. Another bag carrying identical equipment is now being shared by Piper and Bowen.' Luckily they had a spare."
Footage of the incident (Score:5, Informative)
The Grease (Score:3, Informative)
Re:Footage of the incident (Score:5, Informative)
there is footage (Score:3, Informative)
i saw it on nbc this morning
its a top down point of view of the astronaut. she sets the toolbag to the side and addresses some other piece of equipment in front of her, and the bag slowly drifts down, in camera view
by the time she turns her attention back to it, you can see the shock in her hand gestures trying to grab it, now below her waist. i guess space suits don't provide bend
Re:I was just wondering (Score:4, Informative)
If you let go of an object while in orbit, it doesn't just hover in that exact spot over the earth and wait for you to come back around. If it did, then the shuttle/ISS would likely collide with that object at a very high speed and it'd be game over. I'm not sure if that's what you're implying, but it certainly doesn't work that way
The tool bag or whatever is orbiting the earth at the same speed as the astronaut. If I was that astronaut and I lightly pushed my tool bag away, it would mostly continue in the same orbit that it and I had before, plus it would have a small bit of momentum in whatever direction I shoved it. If I only pushed it lightly, then relative to me it would only be moving away very slowly. If it's moving away from me at one mile per hour, then after a 90 minute orbit, then it would be a mile and a half away from me, still moving away at that same speed.
I guess theoretically, if you ignore any sort of air resistance causing orbital decay, if you shoved the toolbag in a direction that didn't change the altitude of the bag in relation to the earth, then it might eventually your path again, but it's not likely to happen.
Link to video (Score:2, Informative)
Re:I was just wondering (Score:5, Informative)
I think the original poster may be correct on this one.
He was not implying that the object would stay still, rather that after the 'shove', the object would now be in a different orbit. The two orbits initially intersect at the point that the 'shove' finishes and no more force has been exerted in changing it's orbit.
Now picture two orbital paths around the planet, but one is at a slightly different angle to the other. They intersect at 2 points, 180 degrees apart. Therefore, the object would stop moving away, relative to you, after 1/4 an orbit. After half an orbit, the orbits would intersect again and you could pick up the spanner.
This, of course assumes that the 'shove' only had a lateral (left/right) component. Any component of force that was up,down, forwards or backwards relative to the initial direction of traffic would complicate that a lot and I do not know how to "in my head" work that out.
The chances of *only* giving the tool a force in the correct plane is, however, pretty unlikely, so the spanner is likely lost for sure.
Tom...
Re:And in today's episode of "guess the acronym" (Score:3, Informative)
Re:I was just wondering (Score:4, Informative)
Eventually they'll deorbit and burn up, but probably not for a while. The tools were in a stable orbit when they were dropped and they weren't thrown very hard (just enough so they were out of reach by the time it was noticed). It takes quite a bit more delta-v than that to deorbit.
Air resistance will get it in a couple weeks at most.
Something the size and density of a space suit takes about six weeks to deorbit due to air resistance at the ISS altitude.
It's an interesting thing to consider, will the much smaller tool bag with its vastly inferior surface area to volume ratio compensate for the (probably) higher density of the tool bag? It is smaller, so it should deorbit much faster because it has much more surface are per volume thus more air drag. On the other hand, the metal tools in the bag are probably somewhat denser than an old space suit.
The ISS has about a pound of force from air resistance, roughly. The toolbag has probably a thousandth the surface area, but probably only a millionth the weight. So it'll probably deorbit about a thousand times faster than the ISS. I am guessing this guess is only accurate to maybe two orders of magnitude.
I'm heard that a hot air balloon (just the fabric canopy) would deorbit in about a revolution due to air resistance, whereas a steel I-beam, pointy end forward (good luck due to gravity gradient stabilization) would not deorbit for decades. That claim that I heard is probably off by even more orders of magnitude.
See link below about the suitsat launched from the station, pictures, how long it lasted, etc.
http://www.amsat.org/amsat-new/articles/SuitSat/ [amsat.org]
Re:And THIS is why (Score:1, Informative)
Don't try to tell me girls don't do it, because I know plenty of cheerleaders, band members, soccer players and field hockey players who all had to deal with crap as a freshman/rookie. You either grow a thick skin and start hurling back, or you become an alienated target because you think people are picking on you specifically. How can people joke around with someone who is not willing to take the heat and laugh at themselves?
Something tells me you never got the joke. And I posted anonymously because this post will probably be modded into oblivion by all the male IT workers with mod points today who are flocking to your defense because you are a girl.
Re:I was just wondering (Score:5, Informative)
For example, if you push the object backward along the flight path, it will now have a slightly lower velocity which will take it to a lower altitude on the other side of the earth, and then back up to your altitude. But that orbit will have a shorter period, so by the time you get back to the start point, the object will have been and gone.
Also, at the altitudes where the Shuttle flies, you're not truly out of the atmosphere...you're still hitting gas molecules from time to time, and every impact takes a tiny bit of energy out of your orbit, which ever-so-slowly brings it downward; that's why low-orbiting satellites don't stay up terribly long. When you eject an object backwards and lower its orbit, it will dip a little deeper into the atmosphere and incur a tiny bit more drag than you do -- which will prevent it ever getting back up to your height again. When a newly-launched satellite deploys its various antennas and stuff, it often has to eject various covers that protected them during launch, and it ejects them back along the flight path for precisely that reason.
rj
Re:I was just wondering (Score:5, Informative)
Re:I was just wondering (Score:5, Informative)
"A bag on a strap will come back and hit you, wrap around you, your arms, your legs, damage your suit, etc."
For all those above with reasons why it would be a bad idea to tether the bag, it was _supposed_ to be tethered, just as all the tools inside it are tethered to the bag.
Well, exept it already did (Score:5, Informative)
Except, say, to the Russians repairing the ISS with improvised tools, because they lost the original tools. [slashdot.org] Or that guy Ed White, the first spacewalker, who lost a spare glove. Or Piers Sellers who lost a spatula. Or those intrepid souls in 2006 who lost a couple of bolts while connecting an addition to the ISS. Or let's hear it for Jerry L. Ross on STS-88, who managed to lose an anchor socket and a panel into space on the very first spacewalk, then a thermal blanket on the second spacewalk. Etc.
(Though, in all fairness, more fun than guys losing tools was when an Indonesian sat got hit by feces. Literally. That's when NASA stopped dumping their shit in space.)
Or on Earth, you have such fine specimens as Dr. Wesley Meyers, the dentist who managed to kill a patient by dropping a too down his throat (and into his lung.) A second time.
Re:I was just wondering (Score:1, Informative)
What the hell?
If the object has angular momentum, then it has its own gravity.
You mean mass. Angular momentum has nothing to do with gravity!
Why are we even talking about the gravity of such small objects, anyway? Air resistance has a much larger effect...
Re:I was just wondering (Score:5, Informative)
Re:I was just wondering (Score:5, Informative)
>>99.99% of space-walks are tethered
You either greatly overestimated how many spacewalks have taken place or you you are planning for the future:
http://en.wikipedia.org/wiki/List_of_spacewalks_and_moonwalks [wikipedia.org]
We've done 7 untethered spacewalks, so your percentage should probably use 2 or fewer significant digits.
-b