Nicole Rayl, project manager for NASA’s portion of the mission, had said before the launch that in order to gather the data from the animals upon their return, they would need to be “humanely euthanized.” What we’d like to know is what caused the mice to perish while traveling 575 kilometers above the earth. Food? Stress? Air quality? Something else? Did they suffer? The only small consolation for the returning animals is that their death will likely be quick and relatively painless. We doubt information will be released on why many of the mice in particular didn’t make make it. The lizards all came back alive. (Again, their survival will sadly be short lived.) We just hope this is the last time any animal that didn’t dream of growing up to be an astronaut gets sent up to space.