NASA is associated with space and the other thing that is related to space, however, it is also known for carrying out unique experiments and researches as well. One of the new research that was carried out by NASA has come up with some of the most interesting results. NASA had sent one of the siblings from a pair of identical twin astronaut named as Scott and Mark Kelly. One of them had spent about 25 months in the International Space Station while the other was on Earth. Now that the siblings are together once again there are some changes that can be noticed varying from one to the other.