First bacteria proved to survive in space

From 2015 to 2018, scientists from the Institute of Space and Astronautical Science, Tokyo, Japan conducted experiments with dried pellets of Deinococcus bacteria. The bacteria were stuffed into small wells in metal plates, which NASA astronaut Scott Kelly affixed to the exterior of International Space Station with samples were sent back to Earth each year. Once back on Earth and rehydrated, the bacteria in 100-micrometer-thick pellets died and the outer layers of 500- and 1,000-micrometer-thick pellets were also killed. However, approximately 4 percent of the microbes in those larger pellets survived and by extrapolating from survival data after one, two and three years of exposure, the scientists estimates that 1,000-micrometer pellets could survive eight years floating through space.

The analysis report was released in August 2020 and demonstrates that living organisms may survive journeys through space if colonies of bacteria etc clump together.