NASA studies twins Mark and Scott Kelly about the effects of space on the human body and mind. (Photo : NASA)
Retired NASA astronaut Mark Kelly uses his laptop in his home in Arizona to give himself a series of memory tests every few weeks. Meanwhile, identical twin Scott Kelly also uses the same tests on his laptop who is located more than 200 miles above the Earth at the International Space Station.
The Kelly twins who are both age 51 are involved in NASA's first human experiment called the Twins Study to assess the long term effects of space radiation on humans including microgravity conditions on physical and mental states.
This experiment will end in March 2016 where Scott Kelly's duration is space will end along with fellow space explorer Russian cosmonaut Mikhail Kornienko who are both now spending a year up in the orbiting space laboratory. Scientists will be ready to analyze this new data from the astronauts where the space agency is about to embark on a round trip to Mars where the journey could take as long as three years.
On Tuesday, September 14, Kelly's stay marks its halfway point at the ISS where he and Kornienko are participating in NASA's one year in space mission. When Kelly returns, he breaks the record for the first American to spend the most time in space than any U.S. astronaut.
In this twins experiment however, the Kellys are required to provide blood samples along with saliva and other body fluids. They will also undergo MRIs and ultrasound tests for researchers to study how space time can affect bone density, cell tissue and DNA markers. Currently scientists are studying their fluid shifts in the upper body in a weightless environment.
NASA has chosen the twins since not only do they share plenty of genetic traits but they also had similar careers in life where they were both Navy pilots and became astronauts in 1996.
Among the experiments involved are telomeres that are tiny molecular "caps" located at human DNA ends. Back on Earth, telomeres are lost due to the effects of old age but NASA believes that telomere loss can become more severe in space due to cosmic radiation. In other words, this experiment will determine if people do age faster in space.
In another experiment, scientists also examine how space damages human vision where astronauts suffer this temporary side effect at the space station. Researchers also administered cognitive tests on the Kellys every few weeks in order to study "space fog", a term astronauts use, citing a lack of alertness during their time spent in space.
