I'm writing a story, and in one part I have one of my main characters, who is a fairy, come to Earth. I want to make the gravity lighter on the planet where she comes from, but I need to know how much lighter I can make it before she starts having dangerous side effects from being on Earth. what would the lasting effects be? would it be possible to make the difference significant enough that she wouldn't be able to fly on Earth?
closed as primarily opinion-based by Aify, Hohmannfan, Thucydides, JDługosz, bilbo_pingouin Jun 13 '16 at 7:16
Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise. If this question can be reworded to fit the rules in the help center, please edit the question.
This question is very flexible, so you can just define the answer yourself:
"You're a fairy? How come you can't fly?" says Jim.
"I can in my world, but I feel... heavy, in this one. My wings aren't strong enough." says Fairy.
It's not really a matter of gravity and specific science, it's more a matter of how strong the fairy is.
As stated already, there is no correct answer for this as it depends entirely on your interpretation. I assume it would be good to know how much gravitational force humans can live with, and I've only found a source stating that somebody withstood 2Gs for 24 hours.
It also states that there is a cap at 4G, at which the brain would not be oxygenated properly. Maybe this can give you some inspiration.
There has been done quite a bit of studying regarding lower gravity, however. Maybe this could give you some hints as to what physiological changes to expect when gravity changes in general.