A pair of U.S. and Russian resupply ships have departed the International Space Station this week. Russia’s Progress 71 (71P) cargo craft undocked this morning and the SpaceX Dragon returned to Earth Monday.
The 71P, packed with trash and unused hardware, undocked from the aft end of the Zvezda service module today at 3:40 a.m. EDT. It reentered Earth’s atmosphere and safely burned up over a remote portion of the Pacific Ocean. This completes a mission that began when the 71P launched Nov. 16 and delivered almost three tons of cargo two days later to the Expedition 57 crew.
SpaceX‘s Dragon cargo spacecraft splashed down in the Pacific Ocean at 5:48 p.m. EDT (2:48 p.m PDT), approximately 202 miles southwest of Long Beach, California, marking the end of the company’s 17th contracted cargo resupply mission to the International Space Station for NASA. The spacecraft returned more than 4,200 pounds of valuable scientific experiments and other cargo.
Some of the scientific investigations Dragon returned to Earth include:
Observing Protein Crystal Growth
NASA’s Biophysics-6 experiment looks at the growth of two proteins of interest in cancer treatment and radiation protection. Scientists are using ground-based predictions and in-space X-ray crystallography to determine which proteins benefit from crystallization in microgravity, where some proteins can grow larger and with fewer imperfections.
Microalgae Biosynthesis in Microgravity
Microalgae Biosynthesis in Microgravity (MicroAlgae) studies the effects of microgravity on Haematococcus pluvialis, an algae capable of producing a powerful antioxidant, astaxanthin. It could provide a readily available dietary supplement to promote astronaut health on long-duration space exploration missions. A community college student and alumnae of the NASA Community College Aerospace Scholars (NCAS) program proposed the research, and NCAS is engaging community colleges across the U.S. to conduct ground studies for comparison to the in-orbit investigation.
Genes in Space
On May 23, astronauts aboard the space station successfully edited DNA using CRISPR/Cas9 technology for the first time in space, working on the Genes in Space-6 investigation. This milestone advances understanding of how DNA repair mechanisms function in space and supports better safeguards to protect space explorers from DNA damage. Genetic damage caused by cosmic radiation poses a serious risk to space travelers, especially those on long-duration missions to the Moon and Mars. CRISPR/Cas9 now joins a growing portfolio of molecular biology techniques available on the ISS National Lab.
These are just a few of the hundreds of investigations aimed at keeping astronauts healthy during space travel and demonstrating technologies for future human and robotic exploration beyond low-Earth orbit, including missions to the Moon by 2024 and on to Mars. Space station research also provides opportunities for other U.S. government agencies, private industry, and academic and research institutions to conduct microgravity research that leads to new technologies, medical treatments, and products that improve life on Earth.
For more than 18 years, humans have lived and worked continuously aboard the International Space Station, advancing scientific knowledge and demonstrating new technologies, making research breakthroughs not possible on Earth that will enable long-duration human and robotic exploration into deep space. A global endeavor, more than 230 people from 18 countries have visited the unique microgravity laboratory that has hosted more than 2,500 research investigations from researchers in 106 countries.
The SpaceX Dragon cargo spacecraft was released from the International Space Station at 12:01 p.m. EDT after flight controllers in Houston delivered remote commands to the station’s Canadarm2 robotic arm. Expedition 59 Flight Engineer David Saint-Jacques of the Canadian Space Agency monitored Dragon’s systems as it departed the microgravity laboratory.
Next up, Dragon will fire its thrusters to move a safe distance from the station and execute a deorbit burn around 4:56 p.m. to leave orbit. Splashdown down is targeted for approximately 5:55 p.m. EDT (2:55 p.m. PDT).
Dragon was detached from the Earth-facing port of the Harmony module at 8:30 a.m. after flight controllers at mission control in Houston delivered remote commands to the station’s Canadarm2 robotic arm. Expedition 59 Flight Engineer David Saint-Jacques of the Canadian Space Agency will back up the operation and monitor Dragon’s systems as it departs the orbital laboratory.
After firing its thrusters to move a safe distance away from the station, Dragon will execute a deorbit burn around 4:56 p.m. to leave orbit, as it heads for a parachute-assisted splashdown in the Pacific Ocean, 202 miles southwest of Long Beach, California, at approximately 5:48 p.m. (2:48 p.m. PDT). There will be no live coverage of deorbit burn or splashdown.
Dragon launched on the SpaceX Falcon 9 rocket May 4 from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida, and arrived at the station two days later with almost 5,500 pounds of science, supplies and cargo on SpaceX’s 17th commercial resupply mission to the station for NASA.