Newly Expanded Space Station Crew Tackles Research and EVA Spacewalk Preparation

NASA Flight Engineer Reid Wiseman photo showing Flight Engineers Barry Wilmore (left) and ESA's Alexander Gerst at work in the Kibo laboratory of the International Space Station.

Image Credit: NASA

The International Space Station’s Expedition 41 crew, which doubled the number of humans in space when three new crew members arrived last week, began its first full work week schedule as a six-person crew Monday with biological research and preparations for a pair of U.S. spacewalks.

Alex Samokutyaev

Flight Engineers Barry Wilmore, Alexander Samokutyaev and Elena Serova joined their Expedition 41 crewmates on the station early Friday following a six-hour, four-orbit trek aboard their Soyuz TMA-14M spacecraft from the launch site at the Baikonur Cosmodrome in Kazakhstan.

Wilmore, Samokutyaev and Serova are slated to spend 5 ½ months aboard the station.

Max Suraev

Commander Max Suraev and Flight Engineers Reid Wiseman and Alexander Gerst, who arrived on May 28, will return to Earth in November.

Shortly after the usual 2 a.m. EDT reveille, the entire crew conducted body mass measurements, inspected their orbital home and participated in a daily planning conference with the flight control teams around the world to review the day’s activities.

Yelena Serova

For Wiseman, Gerst and Wilmore, most of those activities were centered primarily on gearing up for their upcoming spacewalks.

During an Oct. 7 excursion outside the station, Wiseman and Gerst will transfer a previously uninstalled pump module from its temporary stowage location to the External Stowage Platform-2.

The two spacewalkers also will install the Mobile Transporter Relay Assembly (MTRA) that adds the capability to provide “keep-alive” power to the Mobile Servicing System (MSS) when the Mobile Transporter is moving between worksites.

Wiseman and Gerst spent some time reviewing the procedures for that spacewalk and later participated in a conference call with spacewalk specialists on the ground.

Wilmore meanwhile began “scrubbing” the cooling loops of the U.S. spacesuits, including the Liquid Cooling and Ventilation Garment that he will wear under his own spacesuit when he joins Wiseman for the second Expedition 41 spacewalk on Oct. 15.

Wiseman completed the spacesuit water recharge in the afternoon and Gerst checked in on the Zebrafish Muscle study.

Zebra Danios

He assessed the water condition inside the Aquatic Habitat, which is housing a school of spacefaring fish popularly known in the aquarium trade as Zebra Danios.

JAXA's Aquatic Habitat (AQH) on board the ISS

While aquariums provide a relaxing pastime for humans on Earth, recreation is not the goal behind the new Aquatic Habitat, or AQH, aboard the International Space Station.

Instead, researchers will use this unique facility to look at how microgravity impacts marine life.

Sponsored by the Japanese Space Agency, or JAXA, this habitat is a closed-water circulatory system, which provides a new facility option for station research. Scientists will use the habitat to study small, freshwater fish on orbit.

For the first investigations, they plan to examine the Medaka (Oryzias latipes) fish.

Scientists have multiple studies planned to look at the impacts of radiation, bone degradation, muscle atrophy, and developmental biology.

The investigations could last up to 90 days and provide data that may lead to a better understanding of related human health concerns here on Earth.

"We think studies on bone degradation mechanisms and muscle atrophy mechanisms are applicable to human health problems, especially for the aging society," said Nobuyoshi Fujimoto, associate senior engineer at JAXA's Space Environment Unitization Center.

Medaka fish are ideal specimens for many reasons. They are transparent, making it easy to view the inner workings of their organs. They also breed quickly and easily in microgravity environments, enabling multi-generation studies.

Researchers can take advantage of a variety of genetic modifications to these fish, as well. Finally, scientists already have all of the Medaka genome identified, which makes it easier to recognize any alterations to the fishes’ genes, due to factors like space radiation.

The habitat will reside in the Japanese Experiment Module, or JEM, which is also known as Kibo, or "hope" in Japanese. It will attach to a multi-purpose small payload rack for power and housing.

The AQH launched on July 20, with the third Japanese H-II Transfer Vehicle, or HTV cargo vehicle flight, also called Konotouri.

This facility includes an improved water circulation system that monitors water conditions, removing waste while ensuring proper pressure and oxygen flow rates. The system’s design upgrades are based on lessons learned from previous habitats that flew on space shuttle missions STS-47, STS-65, and STS-90.

"(In order) To keep water quality in good condition for the health of the fish, we had to do many tests on the filtration system, especially the bacteria filter," said Fujimoto. "The special bacteria filter purifies waste materials, such as ammonia, so that we can keep fish for up to 90 days. This capability will make it possible for egg-to-egg breeding aboard station, which means up to three generations may be born in orbit. This would be a first for fish in space."

This habitat will provide automatic feeding for the fish, air-water interface, temperature control, and a specimen sampling mechanism.

There will be two chambers for habitation, each sized at 15 by 7 by 7 cm, holding about 700 cc water and a stabilized area for oxygen that will enable fish to "peck" air.

LED lights will simulate day and night cycles, while two video cameras record images of the fish to downlink to the ground, upon request.

The air-water interface design also makes it possible for the AQH to potentially house amphibians in future studies, though currently planned investigations only use fish.

Small plastic plates at the upper side of each aquarium use a grid structure to trap a small amount of air, injected by the crew at the start of an investigation.

The design, which was tested using parabolic flights, prevents the water from escaping into the microgravity environment.

When researchers are ready for the fish to participate on orbit, they will travel in a special transport container to the station, where the crew will then install them within the habitat for observation.

While the AQH is not specifically an aquarium, hopefully the crew will enjoy a sense of relaxation in viewing the fish as they go about their duties aboard the orbiting laboratory.