SpaceX cargo ship streaks across Florida on the way to splashdown

A SpaceX supply ship blazed a trail through the atmosphere over the southeastern United States Thursday night and splashed down in the Atlantic Ocean east of Florida, returning home with 2.3 tons of research specimens and cargo from the International Space Station.

The late-night re-entry capped a 14-hour flight from the space station that began with an automated undocking from the complex at 9:12 a.m. EDT (1312 GMT) Thursday. The Cargo Dragon spacecraft backed away from the research outpost using pulses from its Draco thrusters.

Astronauts inside the space station monitored the departure, ending the 23rd resupply visit to the complex by a SpaceX cargo ship since 2012.

“I want to give a huge thank you to the SpaceX and the NASA teams for getting this vehicle up to us in great shape with a lot of science and supplies for the ISS,” astronaut Shane Kimbrough radioed from the space station. “The activities associated with SpaceX-23 kept our crew busy over the past month.

“We look forward to hearing about the results of the payloads we interacted with,” Kimbrough said. “Have a safe journey back to Earth.”

The Cargo Dragon capsule coasted around Earth throughout the day before its flight path lined up with the re-entry corridor targeting the mission’s primary recovery area in the Atantic Ocean around 40 miles (65 kilometers) east of St. Augustine, Florida.

The Dragon spacecraft fired its Draco thrusters for nearly 10 minutes beginning at 10:06 p.m. EDT (0206 GMT), slowing the capsule’s velocity just enough for Earth’s gravity to pull it back into the atmosphere.

Flying at some 5 miles (8 kilometers) per second, the spaceship encountered the upper fringes of the atmosphere at 10:45 p.m. EDT (0245 GMT).

Temperatures outside the capsule soared to near 3,500 degrees Fahrenheit (1,900 degrees Celsius). Super-heated plasma trailed the 13-foot-wide (4-meter) spacecraft as aerodynamic forces put the brakes on Dragon’s speed.

The nighttime re-entry was visible across the southeastern United States, along and either side off the spacecraft’s ground track. Sightings were reported in Tennessee, Alabama, Georgia, and Florida.

It was the first night splashdown of a Dragon capsule in the Atlantic Ocean. SpaceX’s previous night re-entries, which are more visible than descents in daylight, targeted splashdowns in the Pacific Ocean or the Gulf of Mexico.

Four main parachutes were programmed to deploy a few minutes before splashdown, which was scheduled for 10:57 p.m. EDT (0257 GMT).

SpaceX, working under a commercial resupply contract with NASA, confirmed a successful splashdown in a tweet, ending this spacecraft’s second trip to the space station.

The company’s “Go Searcher” recovery ship was positioned in the Atlantic Ocean to hoist the capsule on its deck, allowing teams to open the hatch and unload time-sensitive cargo for delivery by helicopter back to science labs at NASA’s Kennedy Space Center.

The recovery vessel will transport the spacecraft to Port Canaveral, then SpaceX will move the capsule to a refurbishment facility at Cape Canaveral Space Force Station. Workers there will unpack the rest of the cargo and prepare the spacecraft for another flight to the space station.

The Cargo Dragon spacecraft returned to Earth with about 4,600 pounds (2.3 tons; 2.1 metric tons) of cargo, according to NASA. The cargo included frozen experiment specimens, including cultures from a Japanese anti-atrophy investigation looking at bio-materials that could slow the loss of muscle in space.

The capsule also returned with biomedical samples in cold stowage for a research investigation into how spaceflight induces changes in liver gene expression, which can effect how the body metabolizes from drugs. Scientists say the experiment could help the development of new treatments that can account for the human body’s adaptations to spaceflight.

Another experiment brought home by Cargo Dragon looked at how liquids behave in containers in microgravity.

Cargo Dragon also splashed down with connector caps and plugs used during spacewalks over the summer to install new roll-out solar arrays outside the space station. The hardware will be stored and launched again for use on future solar array installation spacewalks.

The Cargo Dragon mission, designated CRS-23, launched Aug. 29 from Kennedy Space Center in Florida atop a Falcon 9 rocket, and docked with the station the next day.

The unpiloted cargo capsule ferried 4,866 pounds (2,207 kilograms) of supplies and experiments to the space station on the uphill leg of its mission.

SpaceX’s next Cargo Dragon resupply mission is scheduled for launch in December.

Email the author.

Follow Stephen Clark on Twitter: @StephenClark1.