Our exploration of space is full of wonder — but it's also subject to the ordinary minutia of day-to-day living. When you live aboard the International Space Station, everything from crying to controlling fire has to be handled differently.

So, what can you do in space, and what can't you do? Thanks to the work of astronauts, we now have insights into how to live a somewhat normal life in microgravity.

1. Crying

It's doubtful that astronauts spend their time reading Nicholas Sparks's novels, chopping onions or watching "Marley and Me," but sometimes astronauts get things in their eyes, just like the rest of us. The simple solution would be to "cry it out," but it turns out that’s not possible in microgravity. Astronauts can produce tears, but the tears just stay on the eye. Astronaut Andrew Feustel describes an incident when a flake of anti-fogging solution got into one of his eyes while he was performing a space walk. Feustel was able to use the Valsalva, a spongy block included in space helmets meant to be used during pressure readjustment, to get the tears and the detritus out of his eye. As Col. Chris Hadfield proves in the video above, liquid in the eye does, in fact, just glob together. He notes that, "Your eyes will definitely cry in space. The big difference is tears don’t fall."

2. Having sex

So, what about zero gravity hanky-panky? Can you get a room on the ISS? There are no confirmed reports of astronauts ever having sex in space, although there are steamy rumors. Those rumors are most likely false, because in execution, cosmic coitus would be rather difficult and probably not much fun. Due to microgravity, special equipment would be required. In a video, sex expert Laci Green explains what sex in space would entail. Beyond the logistics of strapping two people together, there's the problem of adequate blood flow to the male genitals (blood flow in space is negatively impacted by gravity). Extraterrestrial whoopee could be compromised by a lack of erection. So, can you have sex in space? In theory, yes, but it would certainly take some doing.

3. Getting pregnant

So, say you and your astronaut partner do overcome the trials and tribulations of knocking space boots, does that mean you can create a baby in space? This is a tricky one, where the answer is probably yes, but as of right now, the likelihood of a fetus making it to term is low. Radiation is mostly to blame. There is more radiation on the space station than on Earth (and in space in general), so it's not the kind of situation that lends itself to a healthy pregnancy. So, for right now, space conception isn't a viable option.

4. Playing with fire

What about fire in space? Does it burn like it does here on Earth? The answer is a hard no, but what it does do is interesting. What makes fire act differently in space than on Earth is the lack of gravity. In space "molecular diffusion" causes fire to burn differently than on Earth. On Earth, fire burns upward, but in space it can burn in literal "balls of fire." In addition to microgravity, the conditions surrounding the fire contribute to its behavior. Furthermore, as the video above from DNews explains, astronauts have discovered an unexplained phenomenon in which "combustion can happen with no visible flames at all," and that discovery is certainly getting scientists all fired up because of its beneficial implications if they can recreate the process on Earth.

5. Using the bathroom

It is true that "everyone poops," even astronauts. After hearing what the astronauts go through to eliminate waste on the ISS, we should all be thankful for our earthbound commodes. Again, gravity is our friend. In order for astronauts to relieve themselves, they have to strap down to a space toilet. For solids, the space toilet uses air to suck the waste down and into a holding tank where it is dehydrated and stored for later disposal. When it comes to number one, both women and men are able to urinate standing up, thanks to a tube system that takes care of business. Technology truly is a beautiful thing.

So, those are some things you can and cannot do in space. As we continue our extraterrestrial adventures, our astronauts will encounter new challenges. As for us earthlings, we should be thankful, because one thing is for sure: gravity really does keep us down to Earth.