the numerous health issues that can impact fully-grown astronauts. To address this, NASA scientists carried out a study to observe how an organism raised in microgravity would adapt upon returning to Earth, and the outcomes indicate that the organism in question may struggle to understand up from down — quite literally.
In 1991, NASA sought to find out how a human born in the microgravity of space, akin to the contemporary ISS, would manage upon their return to Earth. Rather than jeopardize a human life, the researchers opted to send an unusual type of creature instead: jellyfish. While a jellyfish shares little in physical resemblance with humans compared to a chimpanzee, they possess one essential attribute: they can recognize direction with the help of gravity. When the jellyfish returned to Earth, those used in the study were physically okay, but profoundly disoriented, which could signal troubling prospects for any future space-born humans.