Tomorrow morning, SpaceX’s historic mission will come to an end. The Dragon spacecraft – the first privately built vehicle to rendezvous, dock, and deliver cargo to astronauts aboard the International Space Station – will return to Earth at approximately 11:44 AM Eastern.
Dragon’s return won’t be a simple one by any means. Returning to Earth from space is never easy.
Reentry procedures will start early Thursday morning at around 4:00 AM EST. The ISS crew will use the station’s robotic arm to pull Dragon out of its docked position. Two hours later at 10:51 AM Eastern, the robotic arm will release the spacecraft which will fire its engines to exit orbit and begin its fall back to Earth.
As it passes through the thickening atmosphere, the Dragon spacecraft will generate friction. This friction in turn generated heat, causing the spacecraft to become engulfed in flames. At the peak of this fiery phase, Dragon will look more like a comet streaking to Earth as temperatures reach up to 3,000 degrees Fahrenheit (1,650 degrees Celsius).
Despite the heat and fire, Dragon won’t burn up. The spacecraft has a powerful PICA-X heat shield that protects it from the fiery reentry. But that’s not all the heat shield does. By offering such total protection, it makes Dragon the only spacecraft that can currently deliver cargo to and from the ISS. Other cargo vehicles that regularly resupplying the orbiting station, those from Russia, Japan, and the European Space Agency, can carry cargo up but are destroyed once they leave the station.
After the initial reentry, three parachutes will unfurl and inflate to slow the spacecraft’s descent before it splashes down in the Pacific Ocean. Its target is a spot a few hundred miles west of Southern California; a little over 563 miles southwest of Los Angeles. The capsule-style Dragon can’t control its fall, but it will aim for its planned impact point by firing the Draco thrusters during reentry to point the direction of its fall.
The splashdown will mark the end of the historic mission. The unmanned Dragon space capsule became the first commercial spacecraft ever to visit the ISS when it docked on Friday May 25, just three days after launching on SpaceX’s Falcon 9 rocket from Cape Canaveral, Florida.
This landmark flight has gone smoothly. Dragon has met each of its mission milestones with few deviations from its initial flight plan. While attached to the space station, astronauts unloaded 1,146 pounds of cargo from the spacecraft including food and other provisions. It also delivered student experiments and a laptop from Cape Canaveral Florida.
Dragon will return to Earth will 1,455 pounds of cargo astronauts have packed inside. Earth-bound contents include hardware used for experiments, spacewalks, and station systems. SpaceX plans to deliver some high-value experiments back to NASA within 48 hours of splashdown, with the rest of the cargo to be sent to the space agency within two weeks.
Just like in the Apollo days, recovery ships will be waiting near Dragon’s impact point to collect the capsule and haul it back to land as soon as possible.
Great article! It was linked in today’s AIAA Daily Launch e-mail.