Charles A. Lundquist

Consort 1 flight results: A synopsis☆

Consort 1 was the first low gravity materials processing payload to be launched by a commercially licensed rocket in the U.S.A. It carried six experiments which operated as planned during approx. 7 min of suborbital, low gravity flight (10(-5) g) and were returned in excellent condition to the investigators within 4 h of launch. Nearly 150 physical samples supported by measurements and photographs made during the flight were obtained for analysis. In addition to the experimental data returned, the success of Consort 1 demonstrated the ability of industry, working with university centers and government agencies, to rapidly prepare and launch payloads. A brief description of the rocket flight and payload configuration is given. Experiment objectives and methods are described and preliminary results and conclusions are presented.

Vapor deposited organic thin film in microgravity

Organic thin films have been grown in space by effusive ampoule physical vapor transport technique with different growth parameters for the source temperature, transport flux, substrate, seeding, and backfilling. Results described in this paper are based on data from the two United States Space Shuttle Endeavour flights, STS (Space Transportation System)-59 and STS-69, using the moderate temperature facility (MTF) for materials processing in space. The facility consists primarily of the effusive ampoule, in which the thin film growth process takes place, encased in two concentric aluminum cylinders with a vacuum space between them. The MTF has produced thin films of variable quality and thickness across 12 mm diameter substrates. The results are discussed with reference to the growth parameters.

Salt ingestion caves

Large vertebrate herbivores, when they find a salt-bearing layer of rock, say in a cliff face, can produce sizable voids where, over generations, they have removed and consumed salty rock. The cavities formed by this natural animal process constitute a unique class of caves that can be called salt ingestion caves. Several examples of such caves are described in various publications. An example in Mississippi U.S.A., Rock House Cave, was visited by the authors in 2000. It seems to have been formed by deer or bison. Perhaps the most spectacular example is Kitum Cave in Kenya. This cave has been excavated to a length over 100 meters by elephants. An ancient example is La Cueva del Milodon in Chile, which is reported to have been excavated by the now extinct milodon, a giant ground sloth. Still other possible examples can be cited. This class of caves deserves a careful definition. First, the cavity in rock should meet the size and other conventions of the locally accepted definition of a cave. Of course this requirement differs in detail from country to country, particularly in the matter of size. The intent is to respect the local conventions. The characteristic that human entry is possible is judged to be a crucial property of any recognized cave definition. Second, the cavity should be significantly the result of vertebrate animal consumption of salt-bearing rock. The defining process is that rock removed to form the cave is carried away in the digestive track of an animal. While sodium salts are expected to be the norm, other salts for which there is animal hunger are acceptable. Also some other speleogenesis process, such as solution, should not be excluded as long as it is secondary in formation of a cave in question.

A transparent furnace as a commercial research facility

Furnace facilities for materials processing on the International Space Station (ISS) may include the Space Experiment Facility (SEF) which consists of two transparent furnace modules. When SEF is put into operation on ISS, various commercial interests can be satisfied sequentially by scheduled employment of SEF. The CMDS will be the facility manager through whom arrangements can be made for SEF access. Utilizing the transparency of the SEF furnace, real-time observation and control of the crystal growth can be accomplished as demonstrated on the Space Transportation System (STS)-77 mission. The ISS should provide long growth periods which are needed to grow large single crystals in microgravity. One area of particular commercial interest is the acousto-optic filters (AOTF) based on mercurous halide research which would continue on the ISS, research begun on the STS-77 mission. The stability of the thermocouple control has a standard deviation of less than 0.1 °C at temperatures of 573/593 °K. The SEF has ...

Physical vapor transport experiments onboard the Space Shuttle Endeavour

Thin films of an organic nonlinear optical (NLO) material, N,N-dimethyl-p-(2,2-dicyanovinyl) aniline (DCVA), have been grown in space aboard the USA Space Shuttle Endeavour on STS (space transportation system) -59 and STS-69. Similar experiments have been conducted in the laboratory as ground controls and have produced single crystals only. In this paper, preliminary results of the space grown film characterization using the differential scanning calorimetry, differential interference contrast microscopy, Fourier transform infrared spectrometry, visible reflection spectroscopy, x-ray diffraction, second harmonic generation, and stylus profilometry are presented. These techniques have implied that ordered, 3.7 (mu) thick, DCVA films, have been grown on disordered substrates.

Space product development experiment module utilizing the ISS

Furnace facilities for materials processing on the International Space Station (ISS) will include the Space Product Development Experiment Module (SPDEM) which includes a transparent Furnace module and an opaque Furnace Module. The SPDEM is scheduled currently for UF-3 aboard the Materials Science Research Rack(MSRR). Various commercial interests can be satisfied sequentially by scheduled employment of the SPDEM. The CMDS will be the facility manager through whom arrangements can be made for SPDEM access. The ISS should provide long growth periods which are needed to grow large single crystals in microgravity. A typical area of commercial interest is acousto-optic filters (AOTF) based on mercurous halide research which would continue on the ISS, research begun on the STS-77 mission. Another area of commercial interest planned for implementation on ISS is liquid metal sintering of composites to further improve techniques for making better quality materials.

Materials development opportunities

Commercial materials development opportunities on the International Space Station have been the subject of extensive discussions over many years. Most of these have addressed specific examples. However, this discipline is reaching a level of maturity such that a more penetrating analysis of space opportunities is timely. A categorization is presented that first identifies three classes of results and second notes four economic traits. Each specific development opportunity can be placed in a matrix position dictated by the class of its results and by its economic trait.