Lead image: View from the Russian Orbital Segment in January 2022 looking towards the US Orbital Segment — credit: NASA
The start of 2022 saw no let-up for the Expedition 66 crew aboard the International Space Station, who are continuing their busy schedule of maintenance, science, and operations aboard their outpost in low Earth orbit. January saw the installation of new external experiments, a spacewalk by the two Russian crewmembers, the departure of a Cargo Dragon spacecraft, and the deployment of five small satellites.
The International Space Station (ISS) crew currently consists of Roscosmos cosmonauts Anton Shkaplerov – the mission commander for Expedition 66 – and Pyotr Dubrov, with four NASA astronauts: Mark Vande Hei, Raja Chari, Thomas Marshburn, and Kayla Barron. The seventh crew member is Matthias Maurer of the European Space Agency. Expedition 66 began in October, although Dubrov and Vande Hei have been aboard the station for much longer, having arrived in April.
Visiting Vehicles and Exposed Facility Changes
January was a quiet month for visiting vehicle movements, with no new crew or cargo craft arriving and the only departure being that of the CRS-24 Dragon spacecraft. Flying an uncrewed mission under the Commercial Resupply Services (CRS) program, CRS-24 had arrived at the station in late December carrying pressurized and unpressurized cargo for the outpost. Throughout its stay at the International Space Station, CRS-24 was docked to the nadir, or Earth-facing, port of the Harmony module.
The unpressurized cargo in Dragon’s trunk, consisting of a pair of experiments for the US Department of Defense’s Space Test Program (STP), was removed via the Space Station Remote Manipulator System (SSRMS) — the Canadarm-2 robotic arm — with the aid of its Dextre manipulator attachment. Preparations for these operations began before Dragon’s arrival.
Early January saw the SSRMS mobile transporter moved to worksite five, stowing of Dextre tools, and the rotation of an Orbital Replacement Unit (ORU) temporary platform to support the work. An inspection of the trunk to verify cargo placement and lighting conditions took place on 4 January.
The STP Houston 8 (STP-H8) package was removed from Dragon on 7 January and handed off to the Japanese Experiment Module Remote Manipulator System (JEM RMS) which installed it on Exposed Facility Unit 2 (EFU2) of the Kibo module.
Shortly after installation, STP-H8 was activated; however, its redundant power supply tripped a controller in the module’s power distribution unit. This was isolated and the experiment was activated using initially only a single line of power while teams from the Japanese Aerospace Exploration Agency (JAXA) conducted troubleshooting on the backup power supply.
On 10 January, after being powered down, the Atmosphere-Space Interactions Monitor (ASIM) climate experiment was uninstalled from the x-axis starboard deck of the Columbus module and relocated to the nadir side of the platform. This new vantage point will allow ASIM to observe the Earth from a different angle, while also making space on the starboard deck platform for the STP-H7 experiment package.
The operation was completed successfully despite some initial difficulties getting connectors to mate at the new location. With ASIM relocated, 11 January saw the STP-H7 package extracted from Dragon and installed successfully on Columbus. It is expected to remain there for at least a year.
The two STP experiment packages carry suites of instruments and technology demonstration payloads coordinated by the STP’s Human Spaceflight Payloads Office. STP-H7 carries six experiments; these include Configurable Autonomous Sensor Processing Research (CASPR) which will autonomously process images from an iSIM-90 camera system – consisting of a pair of imagers in a binocular arrangement. PIANO, or the Phenomenology Imager and Nighttime Observer, is a 4K by 4K infrared imager that will observe weather and cloud cover at night and study airglow in the upper atmosphere.
Other experiments aboard STP-H7 will use signals from Global Positioning System (GPS) navigation satellites to help study ocean surface vector winds and sea states and test techniques for producing images with the sun in field-of-view. Falcon Neuro is an Air Force Academy experiment that will use a pair of neuromorphic cameras to detect sprites – electrical discharges in the upper atmosphere – and lightning from orbit. Finally, the GAGG Radiation Instrument 1 (GARI-1) is a gamma-ray detector that is being carried to flight-qualify it for use on future military and scientific satellites.
STP-H8 carries three experiments, with its primary instrument being the Compact Ocean Wind Vector Radiometer (COWVR). This is a replacement for the STP’s aging Coriolis satellite, which was launched by a Titan II rocket back in 2003 and continues to provide critical data for monitoring winds over the world’s oceans. COWVR uses a microwave radiometer derived from instruments flown aboard the Jason 2 and 3 ocean science satellites. It was originally intended to have been part of the free-flying ORS-6 mission, but following its cancellation, the decision was taken to fly the instrument aboard the ISS instead.
STP-H8 also carries the Temporal Experiment for Storms and Tropical Systems (TEMPEST), which will study storms by using its own microwave radiometer to study the presence of water vapor in the atmosphere. Its payload complement is rounded out by GARI-2, a twin of the GARI-1 instrument aboard STP-H7.
Transfers of pressurized cargo between Dragon were carried out throughout its stay, with new supplies and equipment being extracted by the ISS crew, who also loaded the capsule items to be sent back to Earth. Cargo transfer operations concluded on 20 January in anticipation of Dragon departing the following day. However, poor weather at its recovery site led to its departure being delayed twice. Dragon finally undocked at 15:35 UTC on 23 January, splashing down off the coast of Florida at 21:05 UTC (16:05 Eastern Time) the following day.
Dragon returned several experiments to Earth, as well as station hardware for inspection, repair, and refurbishment. With its recoverable capsule, the cargo version of SpaceX’s Dragon provides a unique capability to return large amounts of equipment from the station to Earth intact, which had only previously been available via the Space Shuttle before its retirement.
In addition to supplies and equipment for the space station, Dragon had also delivered several CubeSats: miniature satellites built to a form factor based around one or more ten-centimeter cube “units.” On 26 January, five satellites were released from the Nanoracks CubeSat Deployer 22 (NRSCD-22), which had arrived aboard CRS-24, with the Flexible Experimental Embedded Satellite 2 (FEES2), Get Away Special Passive Attitude Control Satellite (GASPACS), Passive Thermal Coating Observatory Operating in Low Earth Orbit (PATCOOL), Daily Atmospheric Ionospheric Limb Imager (DAILI) and the Tethering and Ranging Mission of the Georgia Institute of Technology (TARGIT) being deployed from the station to begin their own missions.
Dragon delivered two further CubeSats in addition to the Nanoracks mission, which were kept aboard the station for deployment at the start of February.
Maintaining a Space Station
Much of the crew’s time on orbit is spent maintaining the space station and carrying out research in its laboratories. With the seven crewmembers the only humans aboard the outpost, they are responsible for all operations that cannot be performed remotely from the ground.
Throughout the month, a running theme for station maintenance was the occurrence of problems with the crew exercise equipment – in particular, the Advanced Resistive Exercise Device (ARED). After a failure, the crew had replaced the equipment’s left upper stop cable at the end of December. At the start of January, the right upper stop cable also failed and required replacement.
On 8 January, the left cable was found to be bent out of shape and needed to be straightened; however, less than four days after this was completed, the cable was again found to be bent. Were the crew to use the equipment for bar exercises without repairing the cable, it would have risked further damage to the device, although it could still be used for other purposes.
After ground controllers reviewed images of the ARED, they found that a tension cap was out of alignment, which the crew confirmed and adjusted. After performing this repair, the crew returned ARED to full operation, but by 20 January, the cable was once more found to be bent and needed to be straightened again. The upper stop cables are expected to last between four months and two years without replacement, although two space units are aboard the ISS should they be needed.
Later in the month, during a routine inspection of hoses on the T2 treadmill, the crew found signs of wear on some of the insulation installed to protect them from the vibrations caused by the treadmill. The crew took photos of the damage to allow engineers on the ground to analyze the situation and determine if any future repairs will be required.
Another piece of equipment that was the focus of troubleshooting early in the month was Microgravity Experiment Research Locker Incubator 3 (MERLIN-3), a cold-stowage unit in the Kibo module. This had stopped responding to commands at the end of December and ground teams were unable to restore it to operations by power-cycling it remotely. The crew confirmed that the device’s screen was on but blank and connected it to a computer so ground controllers could attempt to recover it. These efforts were initially unsuccessful, but on 12 January, controllers were able to gain access and reload the unit’s boot sequence and configuration files, returning MERLIN-3 to operation.
On 12 January, the Progress MS-18 spacecraft, docked at the aft port of the Zvezda service module, performed a 395.4-second thruster firing to reboost the space station’s orbit. This burn imparted a total delta-V – or change in velocity – of 0.73 meters per second, raising the orbit by approximately 1.2 kilometers. Two issues were encountered while the station was being reconfigured for the maneuver, with one of the outpost’s reaction control system (RCS) thrusters reporting a failure twenty minutes before the burn was scheduled to begin – although controllers were satisfied that this would not be a constraint to conducting the reboost and the thruster was indicating a nominal status by the time the maneuver began.
The second incident was one of the truss gimbal assemblies – the Beta Gimbal Assembly 1A (BGA 1A) – stalling when put into auto-track mode for the thruster firing. This put the station into a “no-go” configuration for the reboost, but the assembly was recovered and able to reach its target angle in time for the burn to begin on schedule at 18:24 UTC.
Russian cosmonauts Anton Shkaplerov and Pyotr Dubrov ventured outside the station on 19 January, carrying out a seven-hour, 11-minute spacewalk to commission the Prichal module, the new Russian docking node that arrived late last year. This established connections between Prichal and the Nauka module, installed handrails for future EVAs, removed and relocated docking equipment that was no longer needed after the module’s arrival at the station, and prepared Prichal for visiting spacecraft to dock with it. Surplus hardware was jettisoned from the station to be destroyed when it re-enters the atmosphere.
The EVA was conducted from the Poisk module on the Russian side of the station, with the crew wearing Orlan-MKS spacesuits. The spacewalk began at 12:17:31 UTC and concluded at 19:28:56 UTC with all objectives completed successfully. The first docking with Prichal is expected to be made by the Soyuz MS-21 spacecraft in March.
Between 25 and 28 January, a series of upgrades were carried out across the station’s computer systems. The X2R20 upgrade was applied to twelve of the ISS’s core computers, as well as eight PCs used by the crew.
The tireless work of the astronauts and cosmonauts aboard the ISS — as well as that of controllers, engineers, and program managers on the ground — makes the groundbreaking research carried out aboard the International Space Station possible. With parts of the station having now been in orbit for over 23 years and expected to remain in operation into at least the early 2030s, these tasks are vital to the continuation of the mission.
February is expected to be another busy month, with two US spacewalks scheduled and the Progress MS-19 and Cygnus NG-17 cargo craft both expected to arrive. Preparations for the NG-17 mission are already underway aboard the station with checkout of the robotic arm — which will be used to capture Cygnus as it flies below the station — having already been conducted.