IMAGINE SPENDING A YEAR IN SPACE. WHAT KIND OF PERSON WOULD YOU BE WHEN YOU CAME BACK TO EARTH? HOW WOULD IT CHANGE YOU?
SURE YOU MIGHT HAVE A NEW OUTLOOK ON LIFE, BUT YOUR PHYSICAL BODY WOULD ALSO BE IMPACTED. SCIENTISTS AT NASA DECIDED TO FIND OUT JUST HOW MUCH.
MEET ASTRONAUT MARK KELLY. HE’S SPENT 54 DAYS LIVING IN SPACE ON FOUR MISSIONS BETWEEN 2001 AND 2011. IMPRESSIVE!
AND MEET ASTRONAUT SCOTT KELLY. HE’S SPENT A TOTAL OF 520 DAYS IN SPACE. 340 OF THOSE DAYS WERE ALL IN A ROW FROM 2015 TO 2016. VERY IMPRESSIVE!
DO THEY LOOK A LITTLE SIMILAR? YEAH THEY’RE TWINS. AND DURING SCOTT’S LATEST AND LONGEST TRIP TO SPACE, MARK STAYED ON EARTH. SCIENTISTS TOOK DNA AND OTHER SAMPLES FROM THEM PERIODICALLY TO SEE HOW THE TWO CHANGED OVER TIME WHILE THEY WERE SEPARATED FROM EACH OTHER.
SCIENTISTS ARE JUST NOW STARTING TO RELEASE THEIR FINDINGS. ONE OF THE NEWEST RELEASES SAYS THAT THE DNA OF THE ASTRONAUTS ACTUALLY CHANGES AS THEY ARE IN SPACE. SCIENTISTS FOUND THAT THE CHROMOSOMES OF SCOTT ACTUALLY GREW LONGER. CHROMOSOMES LOOK LIKE STICKS OR KNOTS OF THREAD AND ARE FOUND INSIDE HUMAN CELLS. THEY ARE MADE UP OF PROTEIN AND DNA AND CONTROL YOUR GENES, WHICH ARE THE TRAITS PASSED FROM YOUR PARENTS TO YOU. THE SCIENTISTS ARE STILL TRYING TO FIGURE OUT WHAT EXACTLY THIS CHANGE MEANS FOR SPACE TRAVELERS.
SOMETHING ELSE NEAT THEY FOUND — SCOTT’S TIME IN SPACE, STRETCHED HIM OUT TOO. HE CAME BACK TWO INCHES TALLER AFTER HIS YEAR-LONG MISSION! THIS IS BECAUSE WITH LESS GRAVITY PULLING ON HIM, HIS SPINE WAS ABLE TO EXPAND. ASTRONAUTS THAT RETURN FROM SPACE USUALLY NEED SOME TIME TO READJUST TO WALKING AND BALANCING SINCE THEY HAVEN’T HAD TO DO THOSE THINGS IN SPACE WITHOUT GRAVITY!
OH AND BESIDES BEING TALLER, SCOTT’S NOW ALSO EVEN YOUNGER THAN MARK. WELL HE WAS ALREADY THE YOUNGER OF THE TWO, BY SIX MINUTES, BUT BECAUSE OF ALBERT EINSTEIN’S THEORY OF SPECIAL RELATIVITY, HE IS NOW SIX MINUTES AND 5 MILLISECONDS YOUNGER! EINSTEIN’S THEORY SAYS THAT TIME MOVES SLOWER FOR OBJECTS IN MOTION, COMPARED TO A THOSE STANDING STILL. SO SINCE SCOTT WAS MOVING AROUND THE EARTH IN THE SPACE STATION HE ACTUALLY SPENT LESS TIME THERE THAN MARK DID ON EARTH.
CONFUSED YET? YEAH THAT’S PHYSICS FOR YOU. BUT THE MORE SCIENTISTS STUDY THE IMPACT OF SPACE TRAVEL ON ASTRONAUTS LIKE MARK AND SCOTT THE CLOSER YOU AND I GET TO BEING ABLE TO TAKE EVEN LONGER JOURNEYS TO MARS OR INFINITY AND BEYOND!