How 'spacewalking' underwater made me feel like I was really in space

I was breathing just fine through my life support systems, but I kept feeling an urge to double check that everything was ok with my "spacesuit" before heading out on this "spacewalk." I have worn many different types of spacesuits on Earth during my career, but for the first time in my life, I knew that I couldn’t just stop to breathe the air outside if there were an emergency. That's because I was underwater. On this excursion, I was leading a simulated space mission underwater called SEA ST