Table of Contents

Canadian Experiments

Aquatic Research Facility (ARF)

The Canadian-designed and built Aquatic Research Facility (ARF) is a space laboratory which allows scientists to use its microgravity environment to study and better understand early birth defects, bone calcium loss and ocean ecology. ARF is a joint CSA/NASA project-Canada built the experimental equipment and NASA provided flight opportunities. Both agencies share the results of the experiments carried out on ARF, which flies at least once a year.

The facility itself, built by MPB Technologies of Montreal, is used for many experiments, the first of three which flew during mission STS-77. On board the shuttle are six separate containers, each holding two miniature aquariums, allowing up to twelve experiments to be conducted simultaneously. To ensure that all conclusions are a result of microgravity, a second set of six identical containers is mounted on a rotating plate producing an acceleration that perfectly simulates the gravity conditions on Earth. By comparing the results of the experiments conducted at "0g" (space) with those conducted at "1g" (Earth), gravity effects can be identified. By comparing the results of space experiments with experiments conducted in exactly the same manner on Earth, other aspects of spaceflight (radiation, vibration, magnetic fields) can be studied.

The three experiments selected for mission STS-77, two Canadian and one American, provided an integrated international investigation of early embryonic development, ocean ecology and bone calcium loss. These areas of investigation were selected due to the importance of future applications here on Earth.

The results of the three experiments helped shed new light on the early stages of embryo development, as well as on any disruption or alteration in this process. They also provided previously unavailable data on the critical issue of bone calcium loss in space and assisted in determining the feeding patterns of our aquatic food chain.

ARF, apart from being an ideal laboratory for aquatic experiments, is also equipped to capture video and microscopic recordings of animals both in microgravity and under simulated gravity conditions without disturbing the sample. Temperatures and light levels can be adjusted to suit the species and the experiment. Most important, laboratory materials such as chemical markers can be added to any aquarium under computer control during experiments, without disturbing the other aquariums. The instrument is designed to allow all of these functions to be controlled from the ground or by an astronaut. For the first flight, only astronaut control was used with scientists providing ground support from the control centre. All of this technical capability was built into a single shuttle mid­deck locker, the size of a suitcase. This was one of the most complex miniature payloads to fly on a space shuttle.

Early Birth Defects

Microgravity provides a non­invasive way to study the exact process responsible for correcting abnormalities which occur early in development and may lead to birth defects. Since at its early stages, embryo growth is very similar from one species to the next, the results from these experiments allowed us to closely examine key stages of early development anomalies.

Calcium Loss

Humans and animals lose bone calcium and mass during spaceflight. These changes ressemble the effects of osteoporosis, however in space the entire process occurs over several months rather than over several years as when aging. Within days, the initial changes occur. This allows researchers to develop treatments and management strategies which could not be discovered on Earth.

Ocean Ecology

The small aquatic species such as those studied on ARF are a major part of the food chain and an important link in the ocean ecosystem, which converts 40% more sunlight and CO2 (Carbon Dioxide) than the Rain Forest into living matters. In space, we can understand how water density affects the distribution of these animals, independent of other factors such as water temperature and light level. Knowing how these small yet ever so important animals distribute themselves in our coastal regions will enable us to make more precise predictions as to the life cycle of coastal species. The Principal Investigators have designed experiments to investigate the effects of gravity on aquatic species such as sea urchins, starfish and scallops.

Dr. Heide Schatten from the University of Wisconsin will investigate the effects of gravity on the fertilization process and on the first few stages of development. She will examine sea urchin fertilization and early development. It is known that aquatic species develop on Earth with their heads up but why and how this happens is not understood. She will also closely examine the fertilization process and its potential defects. The experiments conducted may lead scientists to the roots of osteoporosis, muscular dystrophy, and even Alzheimer's disease and therefore enable us to find a cure.

Dr. Bruce Crawford from the University of British Columbia will study development of starfish embryo through all stages, from birth to feeding, in the aquatic environment. He will study how these animals locate the surface of the water using gravity, as well as how the lack of gravity affects bone and calcified tissue development. The experiment conducted will help us understand how animals, including humans, are initially formed and may help to predict and control early human birth defects that are yet not well understood. It will also help us understand how tiny aquatic animals feed themselves so we can begin to understand how to feed and maintain our fish stocks, an important food source.

Dr. Ron O' Dor from Dalhousie University will study loss of calcium in the tissue as well as the feeding patterns of Giant Scallop larvae. Knowledge of the calcification process we gain will enhance our understanding of bone loss, a genuine problem for lengthy space travel, and closely related to osteoporosis here on Earth. Knowledge of gravity effects on feeding and location of scallop larvae will provide critical information to predict changes in the aquatic food chain and help us predict changes in feeding patterns.

Together, these experiments will  provide important information on what goes on during the early stages of development, and will help us pin­point the factors which may disrupt this process. Through these findings, we will also be able to improve our ability to predict and understand feeding and distribution of specific marine species off our costal areas. The yearly voyages of the Space Aquarium will go a long way to solidify Canada's leadership role in the rapidly changing fields of space technology and life sciences.

Atlantic Canada thin Organic Semiconductors (ACTORS)

Launched in May 1996 on board Space Shuttle Endeavour, Atlantic Canada Thin Organic Semiconductors (ACTORS), is a microgravity sciences project from Atlantic Canada. ACTORS is designed to produce enhanced quality organic thin films by using the Physical Vapour Transport (PVT) method. These films could find applications as gas detectors, in computers, in lasers, and in high-performance electronic equipment. The PVT method consists of heating  material (which is at the bottom of an ampoule) so that it vaporizes, and deposits a thin film onto a plate at the top of the ampoule.

ACTORS is sponsored by the CSA's Microgravity Sciences Program, the Atlantic Canada Opportunities Association (ACOA) and the government of New Brunswick. This payload will process a new type of semiconductor organic material prepared by the Université de Moncton's research team, led by Dr. Vo-Van Truong. Using hardware developed by COM DEV Atlantic, the ACTORS organic materials will be processed in space, where the gravitational forces are minimal. Under microgravity, more uniform thin films will be formed; this improvement in uniformity is due to the absence of convection, a phenomenon which influences terrestrial processes. Scientists will be able to compare the thin films produced in microgravity with those produced on earth. A better understanding of the PVT process and the role gravity has in affecting the formation of thin films should lead to improved earth-based manufacturing.

On board STS­77, ACTORS will fly as a Get Away Special (GAS) along with other GAS experiments from the United States, Germany, and China. GAS experiments are low cost means of putting experiments on board the Shuttle because they are located in the Cargo Bay and require very little intervention from astronauts.

GAS experiments are self-contained, fully automated, and supply their own power source, data collection, and processing.

Canadian Float Zone Furnace (CFZF)

The Canadian Float Zone Furnace (CFZF) is a materials science crystal growth facility developed jointly by the Canadian Space Agency (CSA) and the German Space Agency (DARA). This payload was launched in the Spacehab 04 module on board Space Shuttle mission STS-77 by the NASA Office of Space Access and Technology. Twelve materials science experiments using four sample materials will be conducted by scientists from three partner countries during this mission.

The CFZF is designed to allow production of larger samples of industrially important materials; these samples will be large enough to allow evaluation of the space­based processes and to
suggest improvements to ground­based processing.

The four materials which will be processed all have great commercial potential in electronics and optical communications. Bismuth germanate (BGO), one of the experiment materials being developed by Canadian scientists, is being examined as the next generation in high-capacity laser disks for computer storage of the data generated on the information super-highway. Cadmium germanium arsenide (CdGeAs₂), the second material Canadian scientists chose for this experiment, is an extremely efficient laser material which has potential to reduce communications costs as well as having applications in laser surgery used for treating cancer. The two materials chosen by the American and German researchers, Gallium Arsenide (GaAs) and Gallium Antimonide (GaSb), are semiconductor materials with applications in fiber optics and microwave cellular communications.

Provided by DARA, the ELLI Mirror Furnace will use a highly focused light to heat each of the rod-shaped sample materials, up to as much as 1400 ^oC. A slice of the material then melts and forms a molten or float zone between the solid feed material and the solidifying crystal. This process is an improvement from Earth­based crystal growth techniques as no container is required to contain the material being processed, thus eliminating contamination from the container wall.

The use of this process currently remains limited in Earth-based laboratories. One of the major problems is that for many commercially interesting materials, surface tension is low and limits the float zone length to a few millimetres, beyond which the molten zone collapses. By processing these experiments in microgravity however, scientists can avoid this problem and obtain larger, purer crystals.

Canadian astronaut Dr. Marc Garneau and NASA astronaut Dr. Andy Thomas are fully trained in CFZF operation, which they monitored during the mission. However, the majority of the samples were processed via telescience control. This means that data and video downlinked informed the Principal Investigators (PI) at Houston's Ground Control Center of the status of the float zone experimentation. Uplink commanding could control all furnace variables (i.e. temperature), as well as the sequence of the experiments. High-quality colour video cameras and a Nikon 35 mm camera with an automatic or ground-controlled trigger recorded the entire process.

The research teams were led by the following PIs and Co­Investigators:

CSA

• Dr. David Quon and Dr. Nicola Maffei,
  Canada Centre for Mineral and Energy
  Technology (Ottawa, ON);
  Dr. Daniel Labrie and Dr. Vladimir Gelfandbein,
  Dalhousie University (Halifax, NS);

DARA

• Klaus­W. Benz and Dr. Arne Croell,
  University of Freiburg (Germany);

NASA

• Dr. Reza Abbaschian and Carlos López,
  University of Florida (USA).

The CFZF project promotes international collaboration, a cost-effective way to conduct space research, and serves as a model for resource sharing on the International Space Station. The CSA, DARA and NASA interagency partnership is expected to lead to further collaboration in materials science research in microgravity.

Nanocrystal Get Away Special (NANO-GAS)

NANO-GAS is a Space Shuttle payload designed to grow high-quality crystals of an advanced new class of materials called nanoporous crystalline semiconductors ­materials whose atomic structures give them unique adsorption characteristics. Potential applications for this new class of materials include high-precision lasers, computers and other high­performance electronic devices. NANO-GAS (Nanocrystal Get Away Special) was launched in May 1996 on board Space Shuttle Endeavour.

Sponsored by the CSA's Microgravity Sciences Program, NANO­GAS processed 38 samples prepared by the University of Toronto's research team, led by Dr. Geoffrey Ozin. The samples were processed in the reactor chamber developed by COM DEV Atlantic. An increase in the size and quality of nanoporous crystals can be achieved by conducting these experiments in microgravity, where the gravitational forces are minimal. By studying microgravity-produced crystals, scientists hope to eventually grow improved crystals on Earth.

NANO-GAS was one of two Canadian Get Away Special (GAS) experiments flying on mission STS-77, along with others from the United States, Germany and China. GAS experiments are a low-cost means of putting an experiment on board the Shuttle because they are located in the Cargo Bay and require very little intervention from astronauts.

GAS experiments are self-contained, fully-automated and supply their own power source, data collection and processing.