9 Science Facts To Make You Sound Clever At Parties

You can throw this one out in response to pretty much any conversation about space or sci-fi.

The idea that your blood will boil if you are exposed to the vacuum of space comes from the principle that the boiling point of a liquid is lower at lower atmospheric pressure ("this is also the same reason you can't ever make a good cup of tea on a plane" you can drop in, wryly).

The atmospheric pressure in outer space is nil, so surely this would make the blood boil instantly?

Well no. The thing is, unless you have a gaping wound somewhere, your circulatory system is completely sealed and pressurised (hence "blood pressure" being a thing), much like the interior of the spaceship that you've presumably just been flung from.

This pressure will keep the blood in its liquid state, in much the same way atmospheric pressure keeps water liquid on the earth's surface.

This doesn't mean that strolling about the vacuum of space is a particularly good idea, however, as there are plenty of other parts of your body that will sustain damage. This includes the liquid in your eyes and mouth, which will boil.

Although, you should also mention, in your thrilling tale, that this doesn't mean that they get scaldingly hot, quite the opposite in fact as the liquid evaporates into the vacuum.