The US National Aeronautics and Space Administration (NASA) plans to launch its new Fruit Fly Lab (FFL) to the International Space Station (ISS) in 2014 as part of a mission to assess the effects of microgravity and other aspects of prolonged space travel on the organisms. NASA hopes the mission will help scientists to understand how long-term space flight might affect humans.
Because fruit flies resemble humans at the genetic, cellular and biological systems levels, they make good models for biomedical research. But their small size and short generation time make them particularly good models for biomedical research in space. This is partly because space is hard to come by in space, with many projects competing for berths in the ISS. Thousands of fruit flies can be housed in a small cassette, similar in size to a deck of cards. This allows scientists to design experiments involving thousands of individuals, enough to give the tests a high degree of statistical power to detect relevant effects. Furthermore, the effects of space flight can be monitored throughout the flies' entire lifespan and even over multiple generations during a single mission.
Fruit flies were the first animals to be launched into space. In 1947, they blasted off in a V-2 rocket, reaching an altitude of about 68 miles in less than 200 seconds before returning to Earth by parachute.
In contrast, the FFL was custom-designed by scientists at NASA's Ames Research Center (Moffett Field, CA) led by Sharmila Bhattacharya. For the new mission (called FFL-01), it will be transported to the ISS aboard the SpaceX Dragon capsule while carrying about 200 fruit flies; about 10,000 insects are expected to come back 30 days later at the close of the mission. The FFL features NanoRacks centrifuges that allow for flies to be exposed to variable gravity conditions from 1 g (Earth gravity) to fractional g (moon or Mars gravity) to 0 g (weightlessness or microgravity). This enables the use of an in-space control group of flies, whereas previous experiments used a control group housed on Earth instead.
FFL-01 will follow up on results from a 2006 experiment aboard the Discovery Space Shuttle showing that fruit flies reared in space had compromised immune systems (PLoS ONE 6, 1–10; 2011). A second mission, planned for 2015, will assess space travel's effects on the fruit flies' cardiovascular systems. NASA has invited researchers to submit proposals for future projects using the FFL.