A thread about peeing in space has gone viral, because it's a hell of a rollercoaster of discovery.

Author Mary Robinette Kowal wrote a piece for the New York Times about the problems women face during space travel thanks to a space program historically tailored to male astronauts. For a recent example, see how NASA was forced to cancel an all-women spacewalk due to a lack of suits in a suitable size.

As part of the piece, Kowal talked about how in the initial phases of the space program in the 1950s, 19 women were put through testing as potential astronauts. Thirteen passed, and it became apparent that women might be more suitable for space travel than men; they were a smaller payload, had better cardiovascular health, consumed less oxygen, and tolerated G-force and stress better than men. However, the US stopped the program and refused to include them in excursions to space.

NASA went on to write to a 9-year-old girl saying “we have no present plans to employ women on spaceflights because of the degree of scientific and flight training, and the physical characteristics which are required." It's pretty clear that at least in the early years of the space program, women were kept out of space by old-fashioned ground-based sexism.

Some people responded to Kowal's piece claiming that women were unable to go to space due to us lacking technology that would enable them to pee there. 

And thus followed the greatest thread on peeing in space that you'll ever see.

Here's where it becomes clear that men should never be allowed anywhere near space.

It's true that astronauts did keep selecting the wrong sized sheath in some kind of bizarre and misguided attempt to impress ground control. The nicknames of "extra-large", "immense", and "unbelievable", were likely given unofficially by the astronauts themselves, and other names recalled have included "large, gigantic, and humongous”, according to Snopes.

"We have three sizes you know, small, medium, and large – in diameter, and there’s always this little ego thing about which one you do pick," Astronaut Russell Schweickart said in an interview.

"Of course the smart guy picks the right size, because it’s very important. But what happens is, if you get too small a size it effectively pinches off the flow and you just turn yellow because you can’t go; and if, on the other hand you’ve got an ego problem and you decide on a large when you should have a medium, what happens is you take your first leak and you end up with half of the urine outside the bag on you. And that’s the last time you make that mistake."

Pick the right size, men. And so we move (briefly) on to pooping.

Finally, when American women began going into space, NASA had to develop a way for them to pee in space. The solution? Wear a massive nappy. And it turned out that it was better for the men too than peeing into a condom. Who knew?

This next tweet will ruin all the glamor of going to space for you, so brace yourselves, potential astronauts.

Check out the rest of the thread on Twitter, with answers to all your questions on whether farting will propel you in zero gravity, and why astronauts have a pee schedule. It's well worth it.

In the meantime, we leave you with this completely unneeded answer to a question you didn't want to ask.