[InTheArmsOfGod]

For those in the know of course...

1. What is the temperature of space - lets say right above earth?

2. What would happen if we are exposed to space? Why the need to don such cumbersome space suits?

3. What is Space exactly? What is it made up of?


Feel free to add your own later

[simoneaugie]

Right above the Earth, it's really cold. Astronauts wear cumbersome suits so they do not explode because space is a vacuum. But all of my answers may be wrong.

[Capuchin]

1. What is the temperature of space - lets say right above earth?

Temperature is very hard to measure in space, and depends on your definition. As the Earth's atmosphere gets thinner and thinner, it gets colder and colder.

If you went there, you would still be heated by the sun, however since space is mostly vacuum, it contains nothing that really can hold the heat, so temperature as you understand it on Earth doesn't really have a meaning. Mercury is a good example, it's about 700K (~400 Celsius) during the day, and 90K (~-210C) at night. It has no atmosphere to speak off, so this is just heating due to the sun. If you were around Earth, you would maybe be (and this is a guess) something like 200K (~-100C). What you are wearing would change your temperature quite a lot, as black clothing would absorb more of the sun's energy than white would.

In deep space, we detect a microwave radiation that suggests it is at 3.725K (~ -269C), this is radiation that was created in the big bang. So wherever you go in space, you won't be much colder than this (it's still pretty darn cold!)

2. What would happen if we are exposed to space? Why the need to don such cumbersome space suits?

Space is a vacuum. If you were to take a balloon and put it in a vacuum chamber, it would get bigger and bigger until it popped. This is because as the air is evacuated from the chamber, less air particles are hitting the outside of the balloon, but an equal amount are hitting the inside, so this pushes it outwards. Eventually the 2 forces become so unequal that the rubber splits under the stress.

What would happen to you without a space suit? There has been much speculation, since people are somewhat unwilling to actually try it. The commonly accepted answer is that firstly all the air would rush out of your lungs - you shouldn't try to hold your breath. Then you have about 10-15 seconds of "useful consciousness" to try and get back to the spaceship, then you would pass out as your blood boiled. After about 30 seconds you would be very dead. Your muscles would be inflated and red due to the blood boiling, but there wouldn't be many other signs of trauma other than that.

3. What is Space exactly? What is it made up of?

It's made of mostly nothing. There's important stuff called dark energy and dark matter, which we have evidence for their existence, but we don't know what exactly this stuff is. The universe is about 73% dark matter and 23% dark energy. The other 4% is matter that we can see, like hydrogen, helium, and the less abundant elements. If you want to know more about dark matter or energy feel free to ask. It's pretty strange stuff, we certainly haven't got any in a pot that we can say "here's some dark matter". We just know that it must be there from what we observe. However most of the volume of space contains nothing.

I hope the above answers helped a bit.