6. The ISS Has Oxygen Candles
If you remember basic chemistry, candles and fire consume oxygen. But the ISS has special candles that actually produce it.
Just one of them creates enough oxygen to last one person for 24 hours. You don’t use a lighter, however. They’re lit with a special chemical reaction that kicks of the oxygen process.
You can actually buy oxygen candles online though most people on earth will never really need one.