DNA appears to hardy enough to survive in space, researchers from Germany and Switzerland report in PLOS One.
The University of Zurich's Oliver Ullrich and his colleagues placed samples of a DNA plasmid carrying a fluorescent marker as well an antibiotic resistance cassette on different spots of a rocket being shot into orbit.
The flight lasted some 13 minutes, reached an altitude of 166 miles, and included more than six minutes of microgravity. Temperatures also climbed to 130°C in the payload bay and external gas temperatures reached an estimated 1,000°C, though the researchers could not say for sure what temperature their DNA samples were exposed to.
After the excursion, the researchers were able to recover DNA from each application site, with more than 53 percent recovery from screw heads. Additionally, they found that more than a third of the DNA retained its biological function.
"This study provides experimental evidence that the DNA's genetic information is essentially capable of surviving the extreme conditions of space and the re-entry into Earth's dense atmosphere," Ullrich says in a statement.
Previous studies, Scientific American notes, have found that bacteria and fungi on the outside of rock samples attached to capsules and sent into space did not survive, though some studies suggested that bacteria in biofilms could endure life in space.
This new finding, New Scientist adds, has implications for both how spacecraft are sterilized to protect against contaminating alien worlds with Earth-based life and for the search for alien life.