SpaceX cargo capsule splashes down in Gulf of Mexico

A Cargo Dragon capsule backs away from the International Space station Thursday, heading for splashdown in the Gulf of Mexico. Credit: Thomas Pesquet/ESA/NASA

Wrapping up a 36-day mission to the International Space Station, a SpaceX Cargo Dragon capsule splashed down in the Gulf of Mexico Friday night with biomedical experiments, spacewalk equipment, and other hardware returning from orbit.

The unpiloted spacecraft made a parachute-assisted splashdown in the Gulf of Mexico south of Tallahassee, Florida, at 11:29 p.m. EDT Friday (0329 GMT Saturday).

SpaceX confirmed the capsule’s splashdown in a tweet as recovery teams converged on the Dragon spacecraft in the Gulf of Mexico. SpaceX’s “Go Navigator” recovery ship was on station near the splashdown zone to pull the capsule out of the sea.

Once the Dragon capsule is on the deck of the recovery ship, teams will open the hatch and retrieve time-sensitive research specimens for delivery by helicopter to the Kennedy Space Center in Florida, where scientists will begin analyzing the experiments.

The recovery ship will bring the capsule back to Cape Canaveral for refurbishment and reuse on a future cargo mission.

The Cargo Dragon spacecraft undocked from the space station at 10:45 a.m. EDT (1445 GMT) Thursday, two days later than originally planned. Managers ordered the delay to wait for Tropical Storm Elsa to move away from Florida.

The unpiloted supply ship spent 33 days at the space station since docking there June 5, two days after launch aboard a SpaceX Falcon 9 rocket from NASA’s Kennedy Space Center in Florida.

The mission was SpaceX’s 22nd round-trip cargo delivery flight to the space station since 2012. NASA has contracts with SpaceX and Northrop Grumman to fly commercial resupply missions to the station.

On the trip up to the space station, the Dragon capsule delivered more than 7,300 pounds (3,300 kilograms) of cargo, including experiments and upgraded solar arrays. Astronauts Shane Kimbrough and Thomas Pesquet installed and unfurled the roll-out solar arrays on three spacewalks last month.

After unpacking the ship’s pressurized cargo cabin, the station astronauts loaded some 5,300 pounds (2,400 kilograms) of research specimens, experiments, and other equipment for return to Earth, according to a NASA spokesperson.

Experiments returned to Earth included a pharmaceutical investigation from Eli Lilly and Company looking at how gravity affects freeze-dried materials. On Earth, freeze-drying medications for long-term storage results in layers with structural differences, and scientists want to know whether specimens freeze-dried in microgravity on the space station have a different structure.

The Dragon capsule also returned an experiment evaluating how gravity affects the structure, composition, and activity of oral bacteria. The data could help design treatments to combat oral diseases on long-term space missions to the moon and Mars, according to NASA.

Leah Cheshier, a NASA spokesperson, said the Dragon capsule was also loaded wih with spacewalk equipment, including a pistol grip tool, torque wrench, cooling garments, water sampling kits, and spacesuit components, such as gloves.

“I want to say thanks to all the SpaceX and NASA teams and all the scientists, engineers, and researchers who have equipment on this vehicle,” Kimbrough said after the Dragon spacecraft departed the station Thursday. “It was a great vehicle. It kept us busy for this past month doing a bunch of great science.”

The Dragon spacecraft jettisoned its disposable trunk section at 10:41 p.m. EDT Friday (0241 GMT Saturday). The unpressurized trunk hosts the ship’s power-generating solar arrays.

The capsule next fired its Draco thrusters at 10:45 p.m. EDT (0245 GMT) for a nine-minute deorbit burn to slow the craft’s velocity enough to drop back into the atmosphere.

After plunging through the atmosphere with a heat shield to protect against scorching temperatures, the Dragon capsule deployed its parachutes a few minutes before splashdown in the Gulf of Mexico.

This mission was SpaceX’s second resupply flight to use the company’s upgraded Cargo Dragon spacecraft, which is based on the design of the human-rated crew Dragon spaceship. The new version of the Dragon spacecraft is designed to be flown at least five times, up from three missions on the earlier configuration.

It can also carry more cargo than the first-generation Dragon spacecraft.

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