SpaceX sent a Dragon cargo spaceship to the International Space Station atop a Falcon 9 rocket early Sunday, without a human crew but with 20 live mice packed into one of the payloads. The launch from Cape Canaveral Air Force Station in Florida went off without a hitch at 1:52 a.m. ET, one day after rainy weather forced a postponement.
The mice are due to live for a month aboard the station inside a contraption called the Rodent Research Facility, as part of an experiment to measure how zero-gravity affects bone strength. The autonomous Dragon capsule is also carrying the first 3-D printer to go into space, a RapidScat radar instrument to observe wind patterns on Earth, and about 5,000 pounds of additional supplies and equipment. The gumdrop-shaped craft is due to rendezvous with the station on Tuesday. After it's unloaded, the Dragon will be sent back down to Earth with returning cargo, but that's not good news for the mice. Their fate is to be euthanized and dissected in orbit.
— Alan Boyle