Main Bus Switching Unit (MBSU) 2 Remove & Replace (R&R): Friday evening and into Saturday, Robotics Ground Controllers maneuvered the Special Purpose Dexterous Manipulator (SPDM) Arms and successfully removed the failed MBSU 2 and replaced it with a spare. The failed MBSU was then installed onto External Stowage Platform (ESP)-2. After a successful power up and checkout of the new MBSU 2, on Sunday the crew removed the Lab Secondary Power Distribution Assembly (SPDA) Jumper and the Lab Truss Contingency Jumper (LTCJ). The jumpers had been in place since last Thursday to ensure that power was maintained to downstream loads during the R&R. Ground Teams have since brought all ISS Systems back to their nominal power configuration.

Sarcolab-3: Last Friday the crew configured the Muscle Atrophy Research & Exercise System (MARES) in the Columbus module. Today the crew began the third of three two-day operations of joint-NASA-ESA-Russia Sarcolab experiment. The subject will ingress MARES followed by the operator performing ultrasound measurements of the right calf muscle with remote guidance and direction assistance from ground specialists. The subject will then don Percutaneus Electrical Muscle Stimulator (PEMS) for electrical stimulation at rest and during voluntary muscle contraction, and Electromyography (EMG) electrodes to measure calf muscle and tendon response at the ankle (calf muscle insertion). Myotendinous and Neuromuscular Adaptation to Long-term Spaceflight (Sarcolab) investigates the adaptation and deterioration of the soleus (calf muscle) where it joins the Achilles tendon which links it to the heel and carries loads from the entire body. Muscle fiber samples are taken from crew members before and after flight and analyzed for changes in structural and chemical properties. MRI and ultrasound tests and electrode stimulation are conducted to help assess muscle and tendon changes caused by microgravity exposure.

OsteoOmics: The crew began the second of four weeks of planned OsteoOmics operations by changing BioCell media in BioCell Habitat 1. The media in the other four habitats will be changed this week. Crewmembers experience bone loss in orbit stemming from the lack of gravity acting on their bones. OsteoOmics investigates the molecular mechanisms that dictate this bone loss by examining osteoblasts which form bone, and osteoclasts, which dissolve bone. Improved understanding of these mechanisms could lead to more effective countermeasures to prevent bone loss during space missions and in a wide range of disorders on Earth. This may lead to better preventative care or therapeutic treatments for people suffering bone loss as a result of bone diseases like osteopenia and osteoporosis, or for patients on prolonged bed rest.

Light Microscopy Module (LMM) Biophysics 3: The crew configured the LMM for the Biophysics science runs in the Fluids Integrated Rack (FIR). The Advanced Colloids Experiment-Temperature-1 (ACE-T-1) Module and the LMM Control Base was removed from the FIR, the LMM objective lenses were configured and the LMM Petri Base was installed. Investigators will use the results from LMM Biophysics 3 to examine the movement of single protein molecules in microgravity. By studying the crystals of a higher quality that can be grown in microgravity, scientists will be able to better understand their structure and how they work.

Lighting Effects Meter Reading: The crew set up and configured the Light Meter hardware and took readings in the US Lab and the JEM Pressurized Module (JPM). Both modules use the legacy General Luminaire Assembly (GLA). The Lighting Effects experiment hopes to better quantify and qualify how lighting can effect habitability of spacecraft. The light bulbs on the ISS are being replaced with a new system designed for improved crew health and wellness. The Lighting Effects investigation studies the impact of the change from fluorescent light bulbs to solid-state light-emitting diodes (LEDs) with adjustable intensity and color and aims to determine if the new lights can improve crew circadian rhythms, sleep, and cognitive performance. Results from this investigation also have major implications for people on Earth who use electric lights.

Dose Tracker: The crew completed a weekly medication tracking entry in the Dose Tracker application. Dose Tracker documents the medication usage of crewmembers before and during their missions by capturing data regarding medication use during spaceflight, including side effect qualities, frequencies and severities. The investigation is expected to provide anecdotal evidence of medication effectiveness during flight and any unusual side effects experienced.

Fine Motor Skills (FMS): The crew completed a series of interactive tasks during a FMS session today. The FMS investigation studies how the fine motor skills are effected by long-term microgravity exposure, different phases of microgravity adaptation, and sensorimotor recovery after returning to Earth gravity. The goal of the investigation is to determine how fine motor performance in microgravity trends/varies over the duration of a six-month and year-long space mission; how fine motor performance on orbit compare with that of a closely matched participant on Earth; and how performance trends/varies before and after gravitational transitions, including periods of early flight adaptation and very early/near immediate post-flight periods.

Extravehicular Activity (EVA) Preparations: In preparation for Friday’s planned EXPRESS Pallet Controller Assembly (ExPCA) EVA, the crew configured cameras to be used during the EVA. They also configured required tools and hardware and reviewd a video briefing package followed by a Robotics On-board Training session.

Emergency On-Board Training (OBT) Simulator Review: The 49S crew performed this review covering US and Russian Segment fire scenarios as well as depressurization and ammonia emergency scenarios.

Today’s Planned Activities

All activities were completed unless otherwise noted.

PWS1 T61P Software Load

Personal Data Prep for Return

Fluids Integrated Rack Doors Open

Audit of light fixtures in SM, MRM1, MRM2, DC1

[РСПИ]. Delete files from [БЗУ]

EKON-M. Observations and photography

Extravehicular Activity (EVA) Reminder for On-Orbit Fit check Verification (OFV)

Reminder 2 Fine Motor Skills

Tropical Cyclone Hardware Closeout

Acoustic Dosimeter Setup Day 1

Fine Motor Skills Experiment Test – Subject

SM Ventilation Subsystem Preventive Maintenance. Group [В2]

MARES Ankle Shaving Preparation

Human Research Facility Ultrasound 2 set up and power on

Review Emergency OBT Simulator Functionality

OsteoOmics Media Relocate

Glacier Desiccant Swap Alternate

MARES Ultrasound Session Assistance

MARES Ultrasound session

Countermeasures System (CMS) Advanced Resistive Exercise Device (ARED) Cylinder Flywheel Evacuation

Environmental Health System (EHS) Total Organic Carbon Analyzer (TOCA) Water Recovery System (WRS) Sample Analysis

Health Maintenance System (HMS) Automated External Defibrillator (AED) Inspection

Photo TV GoPro Setup

Photo/TV EVA Camera Configuration 1

MARES subject electrodes equipment

Ultrasound 2 Guided Data Export

MARES subject electrodes equipment assistance

Photo/TV EVA Camera Configuration 2

OsteoOmics Media Change

Emergency Onboard Trainer review

SM Ventilation Subsystem Preventive Maintenance. Group [В2]

VIZIR. Preliminary session of the experiment

Water Resource Management (WRM) Condensate Sample Init

Regenerative Environmental Control and Life Support System (ECLSS) Recycle Tank Drain

Nitrogen/Oxygen Recharge System O2 Repress Part 1

Review Emergency OBT Simulator Functionality

Regenerative Environmental Control and Life Support System (ECLSS) Recycle Tank Drain Part 2

SM Ventilation Subsystem Preventive Maintenance. Group А

Countermeasures System (CMS) Treadmill 2 System (T2) Monthly Inspection

Dose Tracker Data Entry Subject

KORREKTSIA. Preparation of cooling agents of ECCO mini container. Handover to USOS for placing into MELFI (FE-5)

For Mini ESA Thermal Container: Insertion of two (out of four) Small Cartridges -29°C into MELFI.

Combustion Integrated Rack Upper Rack Doors Open

Water Resource Management (WRM) Condensate Sample Terminate

On-board Training (OBT) EVA Robotics Onboard Trainer (ROBoT) Session

CASKAD. Manual Mixing in Bioreactor

Combustion Integrated Rack Manifold Bottle Replacement

Regenerative Environmental Control and Life Support System (RGN) Wastewater Storage Tank Assembly (WSTA) Fill

Human Research Facility Ultrasound 2 power off and stowage

Environmental Health System (EHS) – Formaldehyde Monitoring Kit (FMK) Deployment Operations

SARCOLAB. MARES and Laptop Power OFF

Environmental Health System (EHS) Grab Sample Container (GSC) Sampling Operations

Combustion Integrated Rack Upper Rack Doors Close

Environmental Health System (EHS) Total Organic Carbon Analyzer (TOCA) Sample Data Record

Lighting Effects Light Meter Readings Alternate 1

Regenerative Environmental Control and Life Support System (RGN) Wastewater Storage Tank Assembly (WSTA) Fill

On-Orbit Hearing Assessment (O-OHA) with EarQ Software Setup and Test

Nitrogen/Oxygen Recharge System O2 Repress Part 2

Review Emergency OBT Simulator Functionality

Regenerative Environmental Control and Life Support System (RGN) Wastewater Storage Tank Assembly (WSTA) Fill

Extravehicular Activity (EVA) Tool Configuring

LMM MELFI Sample Retrieve

On-Orbit Hearing Assessment (O-OHA) with EarQ Software Setup and Test

Fluids Integrated Rack Doors Open

Regenerative Environmental Control and Life Support System (ECLSS) Recycle Tank Fill Part 3

LMM Biophysics Configuration

CONTENT. Experiment Ops

IMS Update

Fluids Integrated Rack Doors Close

ISS HAM Columbus Pass

OsteoOmics MERLIN Removal

Multi-purpose Small Payload Rack (MSPR) /Group Combustion Module (GCM) Component Activation

Regenerative Environmental Control and Life Support System (RGN) Wastewater Storage Tank Assembly (WSTA) Fill

Completed Task List Items

ExPCA-DOUG Review (Completed GMT 126)

Veggie 03 Pillow Watering and Photo (Completed GMT 126)

USOS crew aids RS crew in handover of empty CTBs (Completed GMT 126)

ESA PAO Recorded Message Crew quarters (Completed GMT 127)

ESA PAO Recorded Message Tour of ISS (Completed GMT 127)

Trash Bag Verify (Completed GMT 127)

Veggie 03 Pillow Watering and Photo (Completed GMT 127)

Replace KTO when full (Completed GMT 127)

USOS crew aids RS crew in handover of empty CTBs (Completed GMT 127)

Tropical Cyclone Untended Operations (Completed GMT 127 and 128)

Ground Activities

All activities were completed unless otherwise noted.

OBT RoBOT EVA support

Three-Day Look Ahead:

Tuesday, 05/09: OsteoOmics media change, EVA Equipment Lock prep part 1, EMU on-orbit fit check, EVA procedures review

Wednesday, 05/10: EVA procedures review, MARES, OsteoOmics media change, OBT ISS emergency simulation

Thursday, 05/11: EVA Equipment Lock prep part 2, EVA procedures conference, EVA tool audit, OsteoOmics,

QUICK ISS Status – Environmental Control Group: