Advanced Nanostep: The crew inserted the Advanced Nano Step Return Bag into MERLIN. Advanced Nano Step, more formally known as Effects of Impurities on Perfection of Protein Crystals, Partition Functions, and Growth Mechanisms, monitors and records how the incorporation of specific impurity molecules affect the development and quality of protein crystals. The crystals grown on the ISS are returned to Earth, and characterized using synchrotron X-ray diffraction. The investigation seeks to improve on the quality and success rate of crystals grown in microgravity.

Confined Combustion: The crew performed fabric sample ignitions with the black baffles installed in the system. Confined Combustion examines the behavior of flame as it spreads in differently-shaped confined spaces in microgravity. Flame spread observations are translated into mathematical models for use in understanding the results and applying them to areas with different shapes. In the recent NASA Saffire project, a large-scale flame spread investigation shows that flames spread more slowly in a large confined space than in a smaller space even if all other environmental conditions are the same (oxygen, pressure, flow speed, etc). The faster flame spread in smaller chambers is suspected to be due to a combination of thermal expansion during combustion and tunnel flow acceleration. Radiation heat feedback from chamber walls may also be a factor.

Genes In Space-6 (GIS-6): The crew performed the steps to initiate the GIS-6 Freeze and Fly 2 run 1. Today’s session will help confirm the success of a previous sequence insertion session, as well as attempting to identify specific types of fungi present in the sample. Deoxyribonucleic acid (DNA) damage caused by increased exposure to radiation can affect the long-term health of astronauts. Genes in Space-6 determines the optimal DNA repair mechanisms that cells use in the spaceflight environment. The investigation evaluates the entire process in space for the first time by inducing DNA damage in cells and assessing mutation and repair at the molecular level using the miniPCR and the Biomolecule Sequencer tools aboard the space station.

JEM Water Recovery System (JWRS): The crew checked the simulant urine bag, then re-inserted it into the JWRS unit. During this activity, the crew noted the presence of a bubble at a location where it could have been interfering with fluid flow through a Quick Disconnect (QD). They were able to successfully remove the bubble from this location. The JWRS demonstration will generate potable water from urine using some different, and possibly more efficient, technologies than the water reclamation currently in use on the ISS. In the past on manned spacecraft, urine and waste water were collected and stored, or vented overboard. For long-term space missions, however, water supply could become a limiting factor. Demonstrating the function of this water recovery system on orbit contributes to updating the Environmental Control and Life Support System (ECLSS) to support astronauts on the space station and future exploration missions.

Systems:

SpX-19 Cargo Operations: In preparation for the SpX-19 unberth and return to the ground, the ISS crew took the opportunity today work on Cargo transfer operations. The ISS crew, working off a Cargo Transfer list, packed and transferred a variety cargo items on the Dragon vehicle.

BEAM Cargo Operations: BEAM is currently being used for long-term stowage to help reduce stowage overflow in PMM and elsewhere in nominal ISS stowage locations. Some of the hardware previously stowed in BEAM is due for return or use, so the ISS crew ingressed and removed items for return (ex: HELIOS payload is being returned on SpX-19) or disposal. In addition to retrieving items from BEAM, the crew also backfilled these locations with additional hardware for long term stowage.

Main Bus Switching Unit (MBSU)/Battery Discharging/Charging Unit (BDCU) Packing: With the SpX-19 unberth approaching, the ISS crew prepared both the MBSU and BDCU (previously failed) for return to the ground. The crew reconfigured a removed BCDU and packed into an 8.0 Cargo Transfer Bag (CTB) for return to the ground for a failure investigation. In addition, the crew removed the MBSU from the JEM ORU Xfer I/F and installed the Stanchion Cover on an MBSU for protection during I-Level Maintenance or IVA stowage. The MBSU was placed in a 10.0 CTB and packed with foam for stowage and return.

Completed Task List Activities:

Dragon Cargo Transfer

EVA Procedure Review

Ground Activities:

All activities are complete unless otherwise noted.



Payload Operations Support

Thursday, 12/26 (GMT 360)

Payloads:



Advanced Nanostep

Confined Combustion

Food Acceptability

Genes In Space-6

ISS Experience message review

JWRS bag check

Standard Measures

Systems:

Dragon Transfer and Cargo Ops

ARED Cylinder Flywheel/Valve Foam

CCAA Maintenance Review

MBSU/BCDU Gather, Pack and Stow

Stanchion Tear Down

Regen – EDV Drain Initialize, Swap, Drain Term

OBT Emergency Mask Review

BEAM Ingress, H/W Stow and associated activities

Friday, 12/27 (GMT 361)

Payloads:



Confined Combustion

Food Acceptability

ISS Experience

Rodent Research-19

Standard Measures

SPHERES reswarm prep

Systems:

IFM CCAA R&R

Saturday, 12/28 (GMT 362) – Off Duty Day

Payloads:



No utilization activities

Systems:

No systems activities

Today’s Planned Activities:

All activities are complete unless otherwise noted.