Humans are one step closer to life on Mars. Mouse embryos have been cultured at the International Space Station (ISS) in the first experiment of its kind, suggesting it might be safe for humans to become pregnant in space. More than 700 embryos were extracted from pregnant mice in August 2021 and taken up to the ISS on a SpaceX rocket. Scientists from the University of Yamanashi and the Riken Research Institute in Japan designed a device that allowed astronauts to handle and thaw the embryos over four days, which were then sent back to Earth for testing. They developed normally, despite the high-radiation and low-gravity environment on the ISS. In a statement, the scientists said the study “shows mammals may be able to thrive in space”. The operative word is “may” – they’re calling for more funding for further experiments; including into whether embryos can be created via IVF on the ISS. For its own part, the space station is due for decommissioning (fiery re-entry and splashdown) in 2031.