SpaceX’s CRS-10 resupply mission has enjoyed a smooth period following its somewhat eventful berthing to the Station last month. In the two weeks since the cargo craft arrived at the orbital outpost, the Expedition 50 crew has unloaded all experiments and cargo from the internal and external compartments of Dragon and is now busy reloading the vehicle with experiments and equipment that will return to Earth for recovery later this month.
CRS-10 delivers multitude of experiments:
Given the unexpectedly fun start to Dragon’s time at the Station for CRS-10, which saw a flawless launch from the Kennedy Space Center followed by a rendezvous abort – the first ever for Dragon – during approach to the ISS, the Expedition 50 crew has made quick work of unloading the vehicle of all of its supplies from both inside and outside the spacecraft.
In all, this marks the start of a particularly busy science period for the ISS, with over 300 individual experiments scheduled to be conducted over the next six months.
Moreover, the vast majority of these experiments are slated to be brought to the Station over the course of the CRS-10, -11, and -12 missions (with -11 and -12 launching in April and June, respectively) from SpaceX and the Orbital ATK OA-7 mission later this month.
With the first of these supplies arriving on CRS-10, the Expedition 50 crew got right to work following the Dragon’s berthing on 23 February.
STP-H5 SpaceCube Mini:
On 26 February, the ISS crew removed the Space Test Program – Houston 5 (STP-H5) experiment package from Dragon’s external trunk using the Space Station Remote Manipulator System (SSRSM) – more commonly known as Canada Arm 2 or the Station’s robotic arm.
On 27 February, the crew used the Special Purpose Dexterous Manipulator (SPDM, or Dextre) to remove the Optical PAyload for Lasercom Science (OPALS) experiment from the Express Logistics Carrier 1 (ELC 1) and move it to the Enhanced ORU Temporary (EOTP) platform.
This was done to make room for STP-H5 installation on ELC 1, which was accomplished on 27 February.
Overall, STP-H5 includes numerous payloads for NASA, the U.S. Air Force, and the U.S. Navy: including: the Raven autonomous space navigation demonstration, Lightning Imaging Sensor, and SpaceCube Mini for NASA; the Spacecraft Structural Health Monitoring payload and the Radiation Hardened Electronic Memory Experiment for the U.S Air Force; and two Naval Research Laboratory payloads.
The U.S. Navy experiments will examine the structure, composition, and density of the upper atmosphere and ionosphere while the Air Force’s Spacecraft Structural Health Monitoring payload will examine the effects of space on fasteners and mechanical components of spacecraft.
For NASA, the SpaceCube Mini experiment is a miniaturized version of the SpaceCube 2.0 system – a hybrid computer processor that can provide a 10- to 100-fold improvement in computing power while lowering power consumption and cost.
The SpaceCube Mini experiment will remain attached to the ISS through at least September 2017 (with the goal of remaining on Station for a full year or longer), will validate the advanced onboard processing capabilities for Earth Science/atmospheric chemistry, and will increase the Technology Readiness Level (TRL) of this technology from TRL 6 to TRL 8 while reducing overall programmatic risk of using such technology on future missions.
Previous versions of this experiment have already flown three times – the first aboard Space Shuttle Atlantis on the STS-125 mission to service the Hubble Space Telescope in May 2009, as a SpaceCube on MISSE (Materials on International Space Station Experiment) 7/8, and as a SpaceCube on STP-H4.
Running in conjunction with STP-H4, the -H5 SpaceCube Mini will validate the miniaturized version of the SpaceCube 2.0 system as well as perform real-time onboard Earth science product generation algorithms for atmospheric methane.
Earth- and Space-based applications for this technology included use on future small satellite missions to study and generate a better understanding of climate change, natural disasters, weather, land use, and ecosystem changes.
Continuing with robotic operations within Dragon’s trunk, the Expedition 50 crew removed the Stratospheric Aerosol and Gas Experiment (SAGE) instrument payload (IP) on 2 March and installed it onto the EOTP.
This was followed on 3 March by the removal of the SAGE Nadir Viewing Platform (NVP) from Dragon and the subsequent installation into the trunk of the OPALS experiment – which will be discarded into Earth’s atmosphere when Dragon returns to Earth later this month.
The following day, the SSRMS was commanded through a choreographed sequence that involved stowage of Dextre, with SAGE NVP firmly grasped in Dextre’s Arm 1, on the Power and Data Grapple Fixture 2 (PDGF 2) on the Mobile Base System (MBS) before the SSRMS walked itself from the Node 2 PDGF to the MBS PDGF 1.
The entire Mobile Transporter (MT) was then translated from WS6 (Workstation 6) to WS2.
On 5 March, the SPDM Dextre removed the Robotics Refueling Mission (RRM) payload from ELC4 with Arm 2 before using Arm 1 to place the SAGE NVP experiment on to ELC4.
This was then followed on 7 March by the use of Dextre to remove the SAGE IP from its temporary storage location on EOTP and install the IP onto the SAGE NVP.
SAGE III is a key part of NASA’s mission to provide crucial, long-term measurements that will help humans understand and care for Earth’s atmosphere and is part of NASA’s mission to measure the composition of the middle and lower atmosphere.
Specifically, SAGE III will measure Earth’s ozone layer along with other gases and aerosols by scanning the limb, or thin profile, of Earth’s atmosphere.
In all, SAGE III’s role is to provide global, long-term measurements of key components of the Earth’s atmosphere, the most important of which is the vertical distribution of aerosols and ozone from the upper troposphere through the stratosphere.
SAGE III also provides unique measurements of temperatures in the stratosphere and mesosphere and profiles of trace gases such as water vapor and nitrogen dioxide that play significant roles in atmospheric radiative and chemical processes.
Earth-based benefits of SAGE III include enhancement of our understanding of Earth’s atmosphere and enabling informed policy decisions regarding climate.
Of particular interest for the various science teams that study Earth’s ozone layer and the damage that has been inflicted to it by aerosoles is SAGE III’s ability to confirm just how much progress has been made in reversing ozone layer damage.
Impressively, prior to the start of robotics operations to remove the external elements of Dragon’s payload, the Expedition 50 crew completed the removal of all 1,530 kg (3,373.1 lbs) of internal cargo and supplies within three days of the vehicle’s arrival at the Station.
As stated by the 27 February 2017 ISS daily summary report, “Crew completed unloading the Dragon vehicle on Saturday. Instructions for loading cargo for return will be uplinked to the crew later this week.”
Of the 1,530 kg of internal cargo, 732 kg (1,613.8 lbs) comprises science experiments/hardware for 35 separate investigations sponsored by the ISS U.S. National Laboratory project.
Some of these experiments include: the Merck Microgravity Crystallization Projects (CASIS PCG-5), CASIS Stem Cell Mayo, the Effect of Macromolecular Transport On Microgravity PCG (Protein Crystal Growth), NANOBIOSYM Predictive Pathogen Mutation Study, and Rodent Research-4.
The Merck Microgravity Crystallization Projects, a CASSIS (Center for the Advancement of Science in Space) sponsored PCG experiment, aims to gather information on the impact of the microgravity environment on the structure, delivery method, and purification of KEYTRUDA (pembrolizumab), Merck’s anti-PD-1 therapy.
KEYTRUDA is a humanized monoclonal antibody that works by increasing the ability of the body’s immune system to help detect and fight tumor cells.
Meanwhile, the CASIS Stem Cell Mayo will investigate the microgravity environment of the Station to cultivate clinical-grade stem cells for therapeutic applications in humans.
Currently, there is no safe, reliable, and effective method to rapidly grow certain types of human stem cells on Earth for use in the treatment of disease, and this experiment’s results will help support clinical trials to evaluate the safety and efficacy of microgravity-expanded stem cells as well as support subsequent studies for large-scale expansion of clinical-grade stem cells for the treatment of stroke patients.
The Effect of Macromolecular Transport On Microgravity PCG will test the idea that the improved quality of microgravity-grown biological crystals – or proteins – is the result of a buoyancy free, diffusion-dominated solution environment.
Specifically, the experiment will examine if slower crystal growth rates are due to slower protein transport to the growing crystal surface as well as if the proclivity of growing crystals to incorporate protein monomers versus higher protein aggregates is due to differences in transport rates.
This project seeks to improve the understanding of fluid dynamics and reaction kinetics in microgravity to enhance models of protein crystal growth that will promote utilization of the ISS for drug discovery.
Moreover, the NANOBIOSYM Predictive Pathogen Mutation Study will explore the ability of computational algorithms to predict mutations in the genes of pathogenic bacteria grown in microgravity.
As numerous species of bacteria have evolved resistance to one or more antibiotics used to treat common infections, there is now concern that some bacteria may develop resistance to multiple antibiotics that would make infections by them difficult to eradicate.
Thus, the NANOBIOSYM Predictive Pathogen Mutation Study is a proof-of-concept experiment that will provide data regarding the evolution of antibiotic-resistant pathogens, which will be of significant value to antibiotic drug development.
Lastly, the Rodent Research-4 experiment is part of a broader effort to understand the effects of spaceflight on tissue healing.
Microgravity impairs the wound healing process and has been shown to have negative effects on skin health in astronauts.
Thus, the Rodent Research-4 experiment will attempt to identify the molecular foundations of skin wound healing that are vulnerable to spaceflight-induced stress, potentially unlocking treatment methods for the next generation of wound healing therapies.
Additionally, the experiment could yield new treatment approaches for more than 30% of the patient population that do not respond to current therapeutic options for chronic, non-healing wounds.
Rodent Research-4 will be the first time a comprehensive systems biology approach is used to understand the impact of spaceflight on wound healing.
CRS-10 – coming home:
Currently, the Expedition 50 crew is in the process of loading the CRS-10 Dragon with thousands of pounds of now unneeded cargo, supplies, and trash as well as various experiments and hardware that will be returned to Earth for recovery.
Under the current plan, the CRS-10 Dragon will be unberthed from the Station on 19 March, at which point the vehicle will begin a choreographed sequence to dispose of its trunk before reentering the atmosphere for splashdown and recovery in the Pacific Ocean.
Presently, the next resupply mission to the ISS is Orbital ATK’S OA-7 Cygnus spacecraft, which has been named for former NASA astronaut and the first American to orbit the Earth, John Glenn.
OA-7 is – as of Friday, 10 March, now set to launch on 21 March aboard a United Launch Alliance Atlas V rocket from the Kennedy Space Center/Cape Canaveral Air Force Station within a 30min launch window.
After OA-7, the next resupply flight is slated to be the CRS-11 mission from SpaceX – which is currently targeting liftoff from Launch Complex 39A at the Kennedy Space Center aboard a Falcon 9 rocket on 9 April.
(Images: NASA, SpaceX, CASIS, JAXA)