[WJW]

Dragons are physically impossible in many more ways than the firebreathing. For one, things that large would probably struggle to fly. We can make larger things fly, but have to cheat using jet (or rocket!) engines to generate incredible thrust in ways not typically accessible to living beings.

[andrewflnr]

That's ok, we just need to put them on the moon or somewhere else with lighter gravity.

[onraglanroad]

Less gravity has its own issues. Nothing can fly on the moon :)

[boothby]

And now I'm picturing a dragon with bombardier-beetle style pulsed jet boosters. And while I'd typically question your assumptions of how big dragons need to be in order to deserve the name, I'll assert that quetzocoatlus nothropi[1] was big enough.

[1] https://en.wikipedia.org/wiki/Quetzalcoatlus

[krapp]

"Dragon" as a classification is odd, because when you look at every kind of mythological creature that gets classified as such nowadays, sometimes from cultures that wouldn't have recognized the concept, you find that they have little in common beyond some vaguely reptilian vibe and being scary.

And I'm sorry but that thing is too goofy looking to be considered a dragon.

[Dylan16807]

You can make a setting with denser air and less gravity too.