Main Bus Switching Unit (MBSU) 3 Status: Following yesterday’s MBSU 3 failure, troubleshooting was not successful and the Flight Investigation Team (FIT) determined MBSU 3 is failed. The crew and ground teams coordinated the install of the Node 1 Y-Jumper and Node 1 Contingency Power Jumper and removal of the Node 1 Channel 2 and 3 isolation. This jumper plan recovered all loads except those on DDCU P13A. The current plan is to R&R the MBSU robotically on Thursday, May 2.

SpaceX (SpX)-17 Launch/Berthing Status: Due to yesterday’s MBSU 3 failure, SpX-17 launch is scheduled for May 3 with capture and berthing on May 5.

Kidney Cells: The crew reconfigured the CO2 controller on the Kidney Cells Incubator in preparation of upcoming experiment runs following SpX-17 arrival. This involved swapping the spent CO2 controller from SABL-1. Sable-2 CO2 controller was also rotated. Effects of Microgravity on the Structure and Function of Proximal and Distal Tubule Microphysiological System (MPS), or Kidney Cells, examines how kidney health is affected by microgravity and other factors of space travel, including increased chemical exposure, water conservation and recycling, and altered dietary intake. Serious medical conditions caused by poor kidney health – including protein in the urine (proteinuria), osteoporosis, and kidney stones – occur more often and more quickly in space. Knowledge gained can help protect the health of astronauts and also contribute to better treatments for kidney related conditions on Earth.

Fiber Optic Production: The crew performed a Fiber Optic Production sample exchange and stowed the hardware. Physical Optics Corporation’s (POC’s) Fiber Optic Production investigation creates optical fibers with high commercial value aboard the ISS using a blend of zirconium, barium, lanthanum, sodium, and aluminum called ZBLAN (ZrF4-BaF2-LaF3-AlF3-NaF). Fiber Optic Production operates within the Microgravity Science Glovebox (MSG). Extensive theoretical studies along with a limited number of experimental studies suggest that ZBLAN optical fibers produced in microgravity should exhibit far superior qualities to those produced on Earth. The resulting optical fiber from Fiber Optic Production is expected to help verify these studies and guide further engineering efforts to manufacture high value optical fiber in large volume aboard the ISS.

Space Automated Bioproduct Laboratory (SABL): The crew installed the CO2 controller on the SABL-3 unit. The Space Automated Bioproduct Laboratory (SABL) supports a wide variety of experiments in the life, physical and material sciences with a focus on supporting research of biological systems and processes. It has over 23 liters of temperature controlled volume with LED lighting for scientific hardware and experiments. It can be fitted to provide 5% CO2 for cell cultures and has 2 USB 2.0 ports and 2 Ethernet LAN connections. It also has switchable 28vdc and 5vdc power supplies for experiment use.

Astrobee: Crewmembers reviewed procedures and performed a test fly around of the Astrobee free flyer. Astrobee is a series of three free-flying, cube-shaped robots. The robots are designed to help scientists and engineers develop and test technologies for use in microgravity to assist astronauts with routine chores, and give ground controllers additional eyes and ears on the ISS. The autonomous robots, powered by fans and vision-based navigation, perform crew monitoring, sampling, logistics management, and accommodate up to three investigations.

Advanced Colloids Experiment-Microscopy-2 (ACE-M-2): A crewmember provided photos of ACE Modules so that the ground can verify the viability of the samples prior to science runs. Sometimes it is hard to tell a gas from a liquid. Advanced Colloids Experiment-Microscopy-2 (ACE-M-2) observes the microscopic behavior of liquids and gases separating from each other. The investigation examines the behavior of model (colloid rich) liquids and model (colloid poor) gases near the critical point, or the point at which there is no distinct boundary between the two phases. ACE-M-2 uses a new microscope to record micro-scale events on short time scales, while previous experiments observed large-scale behavior over many weeks. Liquids and gases of the same material usually have different densities, so they would behave differently under the influence of gravity, making the microgravity environment of the International Space Station ideal for these experiments.

Emergency Mask Deploy: Due to emergency masks nearing their expiration, the crew replaced these masks today with new masks that arrived on SpX-16 and NG-11. The seven that arrived on SpX-16 were removed from the Functional Cargo Block [FGB] and seven additional new masks were retrieved from Cygnus. The emergency mask trainers will support future United States Crew Vehicle (USCV) crews.

Caps and Plugs Reconfiguration: The crew reorganized electrical caps and plugs today between the Electrical Caps and Plugs Cargo Transfer Bag (CTB) and the Common Berthing Mechanism (CBM) Control Panel Assembly (CPA) Vestibule Outfitting Kits (VOKs) CTBs. Today’s activity will allow ground specialists to update on-orbit inventories and enable stowage reduction, and cost savings, by returning and re-using excess equipment.

Thermal Amine Scrubber Status: Today, teams initiated Thermal Amine activation and checkout including a power cycle of the Adlink Mini-PC to gain ground telemetry and successful vacuum leak check of all 4 scrubber beds. Activation is ongoing with the checkout of Thermal Amine effectors currently in work.

Portable Computer System (PCS) Zbook Transition: The crew configured and deployed six ZBook laptops, replacing old T61p PCS hardware. The crew does not directly interface with the vehicle management computers as they have no displays or keyboards. Instead, on the USOS, the crew command to the vehicle using laptops called PCS (Portable Computer System). They run on a Linux operating system and are connected to the vehicle 1553 system to act as remote terminals.

Public Affairs Office (PAO) Live Event: Today David answered questions submitted by Canada Youth Summit participants focused on his experiences with space exploration, seeing Earth from space, and the importance of protecting our planet. The Canada Youth Summit will bring together approximately 300 youth, between the ages of 16 and 24, from diverse backgrounds across the country. The purpose of the Summit is to engage youth on issues that are important to them, seek feedback on the Government of Canada’s youth-related initiatives, and highlight the importance of youth service while inspiring youth to serve their communities.

Completed Task List Activities:

ER8 ZBook setup

Ground Activities:

All activities are complete unless otherwise noted.



Astrobee hardware checkout

PCS to ZBook transition

N3 MCA Zero Calibration

Ku Band String 1 Checkout

Look Ahead:

Wednesday, 05/01 (GMT 121):

Payloads:

Life Science Glovebox-crew restraint install and Work Volume deploy(ESA)

Rodent Research-12 Mass Measurement setup (NASA)

Systems:

None planned

Thursday, 05/02 (GMT 122):

Payloads:

Veggie-PONDS reservoir fill (NASA)

RR-12 Mass Measurement Injections (NASA)

RR-12 Habitat Restock and Foodbar exchange (NASA)

BCM Journal (NASA)

Food Acceptability (NASA)

Systems:

Spaceborne computer hardware remove/stow

Today’s Planned Activities:

All activities are complete unless otherwise noted.

