On Jun. 12, 2024, scientists at Weill Cornell Medicine in New York City reported that just a few days in orbit can cause immune-cell disruption, dehydration and cloudy thinking — but most of these conditions revert to normal soon after travelers return to Earth, according to the largest catalogue of data detailing the impacts of space travel on the human body.

The reports aimed to chart how spaceflight affects space tourists, who have a wider variety of health histories than trained astronauts. The study results were published in Nature.