tumblrbot said: ROBOTS OR DINOSAURS?
Robots. Robots are real. Well, except for birds, which are living dinosaurs. Ok, Dinosaurs. I like Owls.
thejakenixon said: If you were to take a sealed zip-lock with no air into it into space on a space walk, could you pull apart the sides so that it would look like there was matter inside of it? Or would it probably inflate a little anyways due to trace amounts of gas still in it from when it was closed?
Funny thing about zip-top bags: They are actually permeable to air and other gases, even through their plastic walls. This is part of how they keep food fresh, and simply due to the thin nature of the plastic. Ever notice how a “freezer” bag is thicker? That’s because it is less permeable (to fight freezer burn).
But you work for NASA, so maybe you have new and improved “space bags” that are truly impermeable to air. Well, even if they weren’t permeable to air, it would be next to impossible to create a true vacuum inside the bag, because true vacuums don’t really exist, even in interstellar space.
Let’s say you ate your space sandwich our of your space bag while inside the International Space Station, sealed it, removing all the air you could (but never all of it, of course), and then took it outside. If the conditions inside the space station are similar to sea level (except for the weightlessness part) then we can calculate exactly what would be in the bag, and the forces at play.
Spoiler: If you leave more than a few trillion molecules of gas in it, the bag will immediately explode when you went outside (it would actually explode inside the airlock). Even a the volume of air just a millimeter above a pinhead would contain about a billion times more air molecules than that. In that best case, air-on-a-pin scenario, you still leave about a millionth of a mole of air inside the bag.
Space is not a complete vacuum, and even in low Earth orbit there’s about 10 nano-Pascals of pressure, or about 10 trillion times less than the air pressure at sea level. At this pressure, exposed fluids spontaneously boil and your flesh would swell or even pop, like an egg in the microwave. Joseph Kittinger, who held the record for highest skydive before Felix “Red Bull” Baumgartner broke his record last year, had a glove malfunction on his dive that resulted in his hand swelling up to nearly twice its size, and he wasn’t even in space.
Temperature in space isn’t the same everywhere either, and can range from very hot to very cold depending on exposure to sunlight. Let’s say you keep your zip-top baggy in the shade, to keep it cold and try to avoid adding extra pressure by increasing the temperature.
So at -100˚ C, with a few micromoles of air in the bag, and with an external pressure of 10 nano-Pascals … that air wants to occupy a seriously big volume. How big?
Well, assuming your space baggy can stretch infinitely without exploding or its molecules stretching so far that it becomes porous and lets all the air out … it would expand to roughly half the volume of the Empire State Building!
Welcome to Night Vale
Episode 37 - The Auction