1,500 fruit flies (Drosophila): These insects were included to study the effects of microgravity on their reproduction and development.

Microorganisms, seeds, and cell cultures: These samples allowed researchers to analyze the effects of radiation and microgravity at cellular and genetic levels.

Unlike its predecessor, BiON-M n. 1, the new satellite traveled in a polar orbit, exposing its passengers to a significantly higher level of cosmic radiation. This choice was crucial for obtaining data on the challenges astronauts will face during future missions to the Moon and Mars, where radiation exposure is one of the greatest concerns.

Results and return to Earth 

After spending approximately 30 days in orbit, the re-entry module of BiON-M n. 2 landed on September 19, 2025, in the steppes of Russia's Orenburg region. The recovery of biological samples is a crucial moment of the mission, as it allows scientists to analyze the physiological and molecular data of organisms exposed to space.

Despite the overall success of the re-entry, not all animals survived. Of the 75 mice sent into orbit, 10 died during the mission. Scientists attributed most of these deaths not to technical problems, but to aggressive behavior among male mice, a finding that, while tragic, still provides important information on animal behavior under stressful conditions.

The preliminary results of the mission are considered of great value for the development of countermeasures and technologies that will protect humans in future long-duration space travel.

Russia's Bion-M 2: Mice and Microbes Headed to Space!

*Board Member, SRSN (Roman Society of Natural Science)
Past Editor-in-Chief Italian Journal of Dermosurgery