CRS-4

After launching Dragon toward the International Space Station, the first stage flew a simulated landing on the Atlantic, braking toward zero speed at the sea surface, but ran out of liquid oxygen during its landing burn. NASA and SpaceX imaged the night-time descent in thermal infrared to study rocket braking at supersonic speed, a technique of interest for landing on Mars.

Dragon itself carried the first 3D printer to be tested in space, along with 20 mice for long-term research.