Dragon splashes down in Pacific with time-critical experiments
SpaceX’s CRS-11 Dragon capsule splashed down at 8:12 a.m. EDT (12:12 GMT) on July 3, 2017, in the Pacific Ocean just off the coast of Baja California after some 28 days attached to the International Space Station.
After being unberthed using the robotic Canadarm2, the craft was moved to a location some 33 feet (10 meters) below the Destiny laboratory module. It was officially released at 2:41 a.m. EDT (6:41 GMT) on July 3 by Expedition 52 astronauts Jack Fischer and Peggy Whitson of NASA.
“Dragon’s been an incredible spacecraft,” Fischer said after release. “I could even say it was slathered in awesome sauce. This baby has had almost no problems, which is an incredible feat considering it’s the first reuse of a Dragon vehicle.”
The CRS-11 Dragon capsule pressure vessel was the same one used during the CRS-4 mission in 2014.
“And the science we’ve done – oh my, the science,” Fischer said. “Most of the 6,000 pounds [2,700 kilograms] of cargo carried was science, and almost all of the return cargo are precious samples for discoveries we can’t wait to see.”
Fischer explained that Dragon also brought up various external experiments too, including an external platform for science, a neutron star analyzer and an experimental solar array that was “rolled out like a party horn on New Years’ Eve.”
“The science on this mission has been non-stop, and we think the scientists will be extremely happy with the volumes of data we gathered for them up here in space in our floating world-class laboratory we call home,” Fischer said. “For the whole SpaceX team, thank you for building such a great vehicle and for finding us some good weather today to allow us to bring home the science on time. Godspeed and fair winds, Dragon-11.”
The spacecraft had originally been planned to splash down on July 2, but due to a forecast of unacceptable sea conditions at the recovery zone, mission managers decided on June 30 to postpone the capsules departure from the station.
Three separate departure burns were performed by the Dragon capsule once the robotic arm released the spacecraft. This gradually pushed the vehicle away from the outpost and outside the 656-foot (200-meter) Keep-Out Sphere (KOS).
Some five hours later, Dragon, using its Draco thrusters, performed a 10-minute de-orbit burn. Minutes after that, its trunk, which is not recoverable, was jettisoned.
A few minutes before splashing down, the capsule released drogue chutes to slow the capsule a bit and to keep a specific attitude for the three main parachutes to be deployed. Once that occurred, along with a successful splashdown, it ensured a successful mission for the first re-flight of a commercial spacecraft to and from the ISS.
Now that Dragon is back on Earth and on a recovery ship, it will now be transported to the port of Los Angeles to offload time-sensitive cargo. The most notable include the Fruit Fly Lab-02 experiment, the Systemic Therapy of NELL-1 for osteoporosis study, and the Cardiac Stem Cells experiment.
The Fruit Fly Lab-02 experiment aims to understand the effects of prolonged microgravity exposure on the heart. According to NASA, because flies are small, have a well-known genetic makeup, and age rapidly, that makes them good models for heart function studies.
For the Systemic Therapy of NELL-1 for osteoporosis study, a group of rodents were used as models to test a drug that can rebuild bone and block additional bone density loss. It is hoped that this can help reduce bone density loss for astronauts on extended stays in space. Additionally, it can potentially help people with osteoporosis.
According to NASA, in-flight countermeasures, like exercise, can prevent bone density loss from getting worse, but nothing on Earth or in space can restore bone density.
Finally, the Cardiac Stem Cells experiment aims to analyze how microgravity affects stem cells and factors that govern stem cell activity. NASA says the study focuses on cardiac stem cell functions and has numerous “biomedical and commercial applications.”
The CRS-11 Dragon was launched June 3 from Kennedy Space Center’s Launch Complex 39A in Florida. After a two-day rendezvous profile, the capsule was berthed to the Earth-facing port of the Harmony module on June 5.
The next Dragon mission will be CRS-12 on Aug. 10, 2017. It is unclear if this capsule will also be a pre-flown vessel.
Video courtesy of NASA
Derek Richardson has a degree in mass media, with an emphasis in contemporary journalism, from Washburn University in Topeka, Kansas. While at Washburn, he was the managing editor of the student run newspaper, the Washburn Review. He also has a blog about the International Space Station, called Orbital Velocity.