WASHINGTON, March 7 (Xinhua) -- U.S. space agency NASA said Friday it has selected 10 proposals for an "unprecedented" twin astronaut study to understand better the effects of space microgravity on the human body.
"NASA's Human Research Program (HRP) will fund 10 short-term, first-of-its-kind investigations into the molecular, physiological and psychological effects of spaceflight in a continuous effort to reduce the health impacts of human space exploration," the U.S. space agency said in a statement.
"The National Space Biomedical Research Institute is partnering with HRP to provide genetic counseling and assisting in the management of the research," it said.
The selected investigations will occur during veteran astronaut Scott Kelly's yearlong spaceflight, the longest space mission ever assigned to a NASA astronaut, aboard the International Space Station beginning March 2015. His identical twin brother, retired astronaut Mark Kelly, will live out his normal life on Earth during Scott's one-year mission.
Scott, who flew two space shuttle flights and a six-month space station mission, will have a cumulative duration of 540 days in low-Earth orbit at the end of his one-year mission aboard the orbiting outpost. Mark, who flew four space shuttle flights, has a cumulative duration of 54 days in low-Earth orbit.
So far, Scot and Mark are the only twins who have both traveled in space.
The investigations will focus in part on the comparison of blood samples collected from Scott and Mark at regular intervals before, during and after the one-year mission, NASA said.
Physiological and psychological testing also will be conducted on the brothers before, during and after the mission.
The 10 investigations, which are from 10 institutions in seven U.S. states, will receive a combined 1.5 million U.S. dollars during a three-year period, said NASA.
Scientific and technical experts from academia and government reviewed a total of 40 proposals submitted in response to a research request announced last August, it added.