SpaceX's Dragon capsule is headed Earth-ward after astronauts aboard the International Space Station released it this morning, reports the AP. The unmanned capsule is laden with some 2,000 pounds of experiments and old equipment, notably some 500 frozen samples of astronaut blood and urine taken over the past year. Dragon is set for a Pacific splashdown this afternoon a few hundred miles off the coast of Baja California. (More SpaceX stories.)