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Space Litter To Hit Earth Tomorrow
A refrigerator-sized tank of toxic ammonia, tossed from the international space station last year, is expected to hit earth tomorrow afternoon or evening. The 1,400-pound object was deliberately jettisoned — by hand — from the ISS's robot arm in July 2007. Since the time of re-entry is uncertain, so is the location. "NASA expects up to 15 pieces of the tank to survive the searing hot temperatures of re-entry, ranging in size from about 1.4 ounces (40 grams) to nearly 40 pounds (17.5 kilograms). ... [T]he largest pieces could slam into the Earth's surface at about 100 mph (161 kph). ...'If anybody found a piece of anything on the ground Monday morning, I would hope they wouldn't get too close to it,' [a NASA spokesman] said."
http://www.reentrynews.com/1998067ba.html
It could be worse, it could be Monday.
Ammonium chloride is not even slightly like ammonia, in the same way that table salt is not even slightly like chlorine gas.
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
TFA says the largest piece could be about 40 pounds and hit at 100 mph. That wouldn't dent your car, it would totally destroy it.
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
The problem is not the desintegration in earth's atmosphere but the uncertainty about where it's going to happen.
Pushing it by a laser would certainly be a more expensive solution but not do anything about the real problem.
"The likes of Facebook and WhatsApp are free to those whose privacy is of zero value."
> It's rare but being hit by metorites *does* happen.
That's my point. six billion people, it's rare that any are hit by all that natural junk, and you are worried about this?
> If something the size of a fridge hit you you'd feel a little bit more than a burning
> sensation!
NASA says no pieces larger than 40lb.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Didn't the american military blast a re-entering spy satellite to pieces a few months ago to see if and tell all others that it could shoot down whatever satellite they wanted to? Ignoring space war treaties? Why couldn't they use the same technique?
Fixed that for you.
The answer? Probably that you end up with even more junk and smaller pieces harder to track.
"The Early Ammonia Servicer (EAS) is a very large, 1400 pound tank of ammonia that was used to cool electronics on the International Space Station (ISS). When a permanent cooling system was installed, the EAS was thrown overboard by spacewalking astronaut Clayton Anderson on July 23, 2007. NASA does not normally dispose of debris by throwing it overboard. The risk of collision with the International Space Station or another satellite does not justify the ease of disposing of debris this way. In the case of the Early Ammonia Servicer, it was too heavy and dangerous (because of the ammonia) to return to Earth in the Space Shuttle, and throwing it overboard was the only option. The EAS has been in a slowly decaying orbit since then." - blatantly copied from an email I received earlier today on this subject.
TFA answers your question. The station has, or had, an ammonia refrigeration system. This tank contained the refrigerant reserve for that.
People have been hit by meteorites. They've also been hit by lumps of ice falling off airliners. Neither is classed as a major hazard, though.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Ammonia, in its pure, gaseous form, is used as a refrigerant. It cools much colder than freon. It's used in industry to freeze meat products, though some have gone to (less effective, but "safer") CO2, which is actually more dangerous. CO2 is less toxic, but NOBODY fails to recognize an ammonia leak.
I hate grammar Nazi's.
If this hit close enough for the ammonia to kill you, the shrapnel would kill you anyway. Ammonia really isn't terribly dangerous. I've had anhydrous leak in my face before. Wasn't pleasant, but wasn't particularly deadly. Hell of a way to die though, I can't imagine how terrible it would hurt to be killed by shrapnel, but have to suffer in a cloud of ammonia while you die. (Ammonia dissolves readily in wounds, eyes, etc. and it burns).
I hate grammar Nazi's.
IANA rocket scientist, but I am a physicist and the physics here is fairly straightforward. No matter how you throw it, if you can't throw it hard enough to enter the earth's atmosphere before it makes it to the other side of the planet, it will go back to the exact same spot you threw it from due to energy conservation. Exceptions only exist if the initial (ISS) orbit is highly elliptical (it's almost circular) so that it processes a lot or if you put a rocket on it, in which case energy conservation behaves less simply. The least energy intensive way of getting it to impact the atmosphere is to throw it backwards so that it's not going fast enough to maintain orbit at that radius and so it will fall toward the earth and hopefully impact the atmosphere. IIRC, this is called a Hohmann transfer orbit. Note that it is not possible to get a object from one circular orbit to another without not one but two impulses, which means you would need a rocket on the trash.
Then stop riding in the goddamn street, motherfucker. It's common courtesy. Ride on the damn sidewalk. go ahead, scaredy-cat. Just try it, I promise that passing policemen will not stop and ticket you.
In Germany, Finland and numerous other countries, cyclists are expected to stay on the sidewalk, and not on the road. They might be ticketed if caught cycling on the road if the road has a sidewalk.
In Great Britain, Ireland, and numerous other countries, cyclists are expected to stay on the road, and not on the sidewalk. They might be ticketed if caught cycling on the sidewalk.
These laws are unevenly enforced.
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
The answer to this has to do more with what the rest of the ISS is doing than the little piece of trash that you are throwing "overboard".
You are completely correct that anything you toss out will eventually come back and hit you no matter how hard you throw it. Well, that is if that is the only thing you have tossed and in a completely pure mathematical sense.
At the ISS altitude you are still somewhat inside the Earth's atmosphere anyway, so everything has a bit of atmospheric drag to it. Yeah, it is so little "atmosphere" that it might as well be the best vacuum you can find on any ground-based laboratory, but getting pelted by air molecules still eventually slow down spacecraft, including the ISS. That is also the reason why this tank is even in the news at all right now.
The ISS has to use thrusters and "boosts" from the shuttle visits to raise the altitude of the station periodically. As soon as this happens, the station is in a completely different orbit from the trash, which can then take its sweet time to crash to the Earth eventually.
Both Skylab and MIR suffered the ultimate consequences of what would happen if you didn't perform this periodic boosting... and ultimately came crashing to the Earth. The ISS is large enough that, at least from what I understand, the partner agencies don't ever want to see that happen.