Your Space Adventure 1: Out in Space without a Space Suit

So you want to go to space?
Let's say you are invited to the International Space Station. We take two scenarios from here:

1. You arrive to the space station, but your colleagues don't like you. They send you to an EVA (Extra-Vehicular Activity a.k.a. spacewalk) without a space suit. Oops. (An impossible scenario, but for now let's just assume this can happen.)
2. Your colleagues love you and make you stay for a half a year. (Much more likely.)

How does your body take all this?  Here it is for Scenario 1:



So you arrived. Welcome to weightlessness! 

You can start enjoying yourself in weightlessness, but most probably you won't really feel like it just yet. Your senses are a little confused and you feel disoriented trying to decide where is up and where is down (while there is no up or down). You might have headaches, lose your appetite, feel nauseated, or worse. But no worries: there is a solution to that worse. Chris Hadfield shows you what to do in case your breakfast wants to come back out:

If you are in the unlucky 2/3 of astronauts, in minutes of your arrival you will experience some of the symptoms mentioned above - they are symptoms of Space Motion Sickness (SMS). Your body is not used to weightlessness yet. But in two days you will feel better, and on the third day you are ready for your EVA.

Out in space - Without a Spacesuit

Your colleagues didn't like you and they sent you to an EVA without a spacesuit. You are thrown out in space and you have really very little time to figure out how to save yourself before you lose consciousness. Here are a couple of things to worry about: heat, cold, radiation, vacuum.

If you are exposed to sunlight, then it's about +140°C. You will get some serious sunburns. If  you are in the shade, then it is very chilly, around -140°C. But you have have some time before you get deep frozen because in space heat does not transfer away from your body so quickly. And there is radiation. But the most worrying of all at the moment is the vacuum of space, you will loose consciousness within 15 seconds, and then, in a couple of minutes, you will suffocate. Holding your breath is not a very good idea, it is likely to fatally damage your lungs.

In 1966, during a spacesuit test in a vacuum chamber at NASA, an oxygen hose became unhooked and the suit started depressurizing, exposing the person inside to near vacuum. He passed out after 14 seconds. Fortunately, his colleges got to him quickly. He reported later that he heard the air leaking out of his suit, and his last memory was that saliva on his tongue started bubbling. This happened because in the near vacuum environment water spontaneously converted to vapor, it boiled away.

The same would happen to fluids in your muscles and soft tissues in outer space without a suit. The evaporating fluids would cause swelling in some parts of your body, unless you get rescued in time ...