NASA @NASA
Spaceflight — in addition to being awesome — causes changes in the human immune system. We are careful w/ our @NASA_Astronauts so they don’t get sick, but we need to ensure their immune systems are strong for longer trips. Learn about this @ISS_Research: https://t.co/NC3cOTkZcF https://t.co/7ZxjspXFVW — PolitiTweet.org