February 21, 2022
On this date in 1964, American astronauts Mark and Scott Kelly were born. Mark and Scott are twins who were a part of a NASA experiment to test the long-term effects of spaceflight on the human body. Scott was chosen to spend a year in space on the ISS, while Mark remained on Earth to be a genetically matched control. This experiment allowed scientists to understand if humans can make long duration flights to places like Mars.
To read more about the Kelly twins and the results of this experiment, visit: https://www.smithsonianmag.com/science-nature/nasas-twins-study-creates-portrait-human-body-after-year-space-180971945/
Mark (left) and Scott (right) are twins who participated in a study on long-term effects of space. Mark remained on Earth, and Scott spent nearly one year in space aboard the International Space Station. Image credit: NASA
