> Being in the “habitable zone” doesn’t mean a planet is habitable True. Being a spooky near twin of Earth isn't necessarily enough. The air inside popcorn fa

> Being in the “habitable zone” doesn’t mean a planet is habitable True. Being a spooky near twin of Earth isn't necessarily enough. The air inside popcorn factories is basically identical to the Earth's atmosphere, but breathing in diacetyl, a butter flavor you'll find in that air, will kill you a few months or years later. Popcorn lung really undermined my naive view that we would one day be able to run a scan or a sniff test on a planet and then just breathe without assistance. https://en.wikipedia.org/wiki/Bronchiolitis_obliterans https://en.wikipedia.org/wiki/Bronchiolitis_obliterans You have an identical twin to Earth with slightly different dust composition and it could shred our lungs. We are highly, highly tuned to our home. Which doesn't mean we can't go anywhere. But it won't just be advances in travel speed that will get us off world. It may also require drastic modifications to the human organism.