The paper proceeds as follows. Section two below discusses the topic of protein crystallization in biomedical research as well as our current understanding regarding the contribution of microgravity in developing better quality crystals. Section three addresses possible policy intervention, also including the introduction of a government funded consortium to diffuse risk. Section four outlines a specific model that has recently been developed by RTI International, which provides an interesting quantitative framework for measuring private sector costs. The outcome of this section is essentially a list of needed data and data sources. Finally, Section five concludes.
Research Containing: NASA
Concurrent flame growth, spread and extinction over composite fabric samples in low speed purely forced flow in microgravity
As a part of the NASA BASS and BASS-II experimental projects aboard the International Space Station, flame growth, spread and extinction over a composite cotton-fiberglass fabric blend (referred to as the SIBAL fabric) were studied in low-speed concurrent forced flows. The tests were conducted in a small flow duct within the Microgravity Science Glovebox. The fuel samples measured 1.2 and 2.2 cm wide and 10 cm long. Ambient oxygen was varied from 21% down to 16% and flow speed from 40 cm/s down to 1 cm/s. A small flame resulted at low flow, enabling us to observe the entire history of flame development including ignition, flame growth, steady spread (in some cases) and decay at the end of the sample. In addition, by decreasing flow velocity during some of the tests, low-speed flame quenching extinction limits were found as a function of oxygen percentage. The quenching speeds were found to be between 1 and 5 cm/s with higher speed in lower oxygen atmosphere. The shape of the quenching boundary supports the prediction by earlier theoretical models. These long duration microgravity experiments provide a rare opportunity for solid fuel combustion since microgravity time in ground-based facilities is generally not sufficient. This is the first time that a low-speed quenching boundary in concurrent spread is determined in a clean and unambiguous manner.
Combustion of clear cast polymethylmethacrylate (PMMA) samples 10 cm long by either 1 or 2 cm wide with thicknesses ranging from 1-5 mm was investigated in opposed flow. Tests included both one sided and two sided burns. The samples were burned in a flow duct within the Microgravity Science Glovebox (MSG) on the International Space Station (ISS) to ensure true microgravity conditions. The experiment took place in opposed flow with a varying oxygen concentration (uncontrolled) and varying flow;velocities (controlled). Flames are recorded on two cameras and later tracked to determine spread rate.;Assuming a linear profile between oxygen concentration at the start and the end of each test we made graphs of oxygen concentration vs. time for each test. From these we created flammability maps showing the flame behavior at different oxygen concentrations and flow velocities. Additionally we have conducted an extinction analysis, plotting the oxygen concentration against the flow velocity at;the time of extinction with respect to type of test (one sided or two sided).;Currently we are modeling combustion of flat PMMA;samples in microgravity using Fire Dynamic Simulator (FDS 5.5.3). The entire modeling for BASS-II is done in DNS mode because of the laminar conditions and small domain. The model employs the same test sample and MSG geometry as the experiment. The model predicts a higher flame spread rate than that observed in experiments. So we look to modify the chemical kinetics and materials;properties to improve the model. Also we plan to do a domain study and grid sensitivity analysis in future.
This paper will explore the opportunities and challenges in developing the commercial market in LEO through the ISS program and all its facets, including operations, mission support activities, utilization, and contracting. The role of NASA-funded research in the vertical translation of basic research in space to practical application in the market or to other government service agencies will also be addressed. Other aspects, including government regulation, investment and tax incentives, and possible roles of various government agencies will also be explored. Of particular importance, the role of private industry, currently in the supply business, in the development of the demand for LEO capabilities and services beyond the federal government will be highlighted. In conclusion, this paper will address the prospects in reaching the goal of commercializing LEO starting from where we are today in human spaceflight and the International Space Station.
Evaluation of rodent spaceflight in the NASA animal enclosure module for an extended operational period (up to 35 days)
The National Aeronautics and Space Administration Animal Enclosure Module (AEM) was developed as a self-contained rodent habitat for shuttle flight missions that provides inhabitants with living space, food, water, ventilation, and lighting, and this study reports whether, after minimal hardware modification, the AEM could support an extended term up to 35 days for Sprague-Dawley rats and C57BL/6 female mice for use on the International Space Station. Success was evaluated based on comparison of AEM housed animals to that of vivarium housed and to normal biological ranges through various measures of animal health and well-being, including animal health evaluations, animal growth and body masses, organ masses, rodent food bar consumption, water consumption, and analysis of blood contents. The results of this study confirmed that the AEMs could support 12 adult female C57BL/6 mice for up to 35 days with self-contained RFB and water, and the AEMs could also support 5 adult male Sprague-Dawley rats for 35 days with external replenishment of diet and water. This study has demonstrated the capability and flexibility of the AEM to operate for up to 35 days with minor hardware modification. Therefore, with modifications, it is possible to utilize this hardware on the International Space Station or other operational platforms to extend the space life science research use;of mice and rats.
This article reports on a collaborative enterprise between Oklahoma State University’s (OSU) NASA Education Projects and OSU’s College of Education preservice elementary teachers (PSTs) to engage approximately 400 middle school students for a 20-minute live downlink with Commander Kevin Ford from the International Space Station (ISS). NASA supports this opportunity through a competitive proposal process (National Aeronautics and Space Administration, 2014). The project’s theme, Pioneers in Space: STEM Careers on the Space Frontier, engaged both PSTs and middle school students in discussing the benefits of space research, while drawing on themes relevant to students’ regional history. PSTs prepared Pioneers in Space instructional units and led classroom activities linking 6th grade state science standards. The desired outcome was to promote a greater understanding of how space exploration benefits society and contributes to STEM innovations. This paper reports on how curriculum design and leadership experiences in space education and outreach impacted the PST participants.
Opposed-flow flame spread: A comparison of microgravity and normal gravity experiments to establish the thermal regime
The thermal regime of flame spread over solid fuels constitutes the reference condition for all other flame spread research. Although the theory of flame spread in the thermal regime is well understood, the well- known closed-form formulas for flame spread do not compare well with available experimental data. The comparison is further complicated by the fact that establishing a thermal regime in a normal-gravity environment is difficult because of the buoyancy induced flow which may usher in finite-rate kinetics effect. As a result, even the transition thickness, when a fuel can be considered a thermally thick fuel, still lacks a widely accepted formula.;In this work we present opposed-flow flame spread data over varying thicknesses of poly-methyl methacrylate (PMMA) obtained in the International Space Station where the opposing flow velocity can be reduced arbitrarily without any interference from the gravity induced flow. We also present a larger set of spread rate data for the downward spreading configuration at normal gravity. A comparison be- tween the two data set allows us to establish the thermal limit for thin fuel for which the spread rate is independent of the opposing flow velocity. The classical thin-fuel spread rate formula is shown to fit well with the experimental results provided the adiabatic flame temperature is used in the flame coefficient that appears in the formula. The experimentally determined flame coefficient along with downward flame spread data for thick fuels are used to develop a closed-form expression for the transition thickness between thermally thin and thick fuels for downward spread in the thermal regime.
Precision Measurement of the Helium Flux in Primary Cosmic Rays of Rigidities 1.9 GV to 3 TV with the Alpha Magnetic Spectrometer on the International Space Station
Knowledge of the precise rigidity dependence of the helium flux is important in understanding the origin, acceleration, and propagation of cosmic rays. A precise measurement of the helium flux in primary cosmic rays with rigidity (momentum/charge) from 1.9 GV to 3 TV based on 50 million events is presented and compared to the proton flux. The detailed variation with rigidity of the helium flux spectral index is presented for the first time. The spectral index progressively hardens at rigidities larger than 100 GV. The rigidity dependence of the helium flux spectral index is similar to that of the proton spectral index though the magnitudes are different. Remarkably, the spectral index of the proton to helium flux ratio increases with rigidity up to 45 GV and then becomes constant; the flux ratio above 45 GV is well described by a single power law.
The University of Colorado is working with NASA to extend Earth's internet into outer space and across the solar system. The new networking technology is called Disruption Tolerant Networking (DTN), and is being tested on the International Space Station. DTN will enable NASA and other space agencies around the world to better communicate with international fleets of spacecraft that will be used to explore the moon and Mars. This technology is evolving into an Interplanetary Internet. In this paper we describe the design and features of the DTN-on-ISS implementation as well as reporting initial results from the experimental deployment.
Robonaut 2, or R2, arrived on the International Space Station in February 2011 and is currently undergoing testing in preparation for it to become, initially, an Intra-Vehicular Activity (IVA) tool and then evolve into a system that can perform Extra-Vehicular Activities (EVA). After the completion of a series of system level checks to ensure that the robot traveled well on-board the Space Shuttle Atlantis, ground control personnel will remotely control the robot to perform free space tasks that will help characterize the differences between earth and zero-g control. For approximately one year, the fixed base R2 will perform a variety of experiments using a reconfigurable task board that was launched with the robot. While working side-by-side with human astronauts, Robonaut 2 will actuate switches, use standard tools, and manipulate Space Station interfaces, soft goods and cables. The results of these experiments will demonstrate the wide range of tasks a dexterous humanoid can perform in space and they will help refine the methodologies used to control dexterous robots both in space and here on Earth. After the trial period that will evaluate R2 while on a fixed stanchion in the US Laboratory module, NASA plans to launch climbing legs that when attached to the current on-orbit R2 upper body will give the robot the ability to traverse through the Space Station and start assisting crew with general IVA maintenance activities. Multiple control modes will be evaluated in this extra-ordinary ISS test environment to prepare the robot for use during EVAs. Ground Controllers will remotely supervise the robot as it executes semi-autonomous scripts for climbing through the Space Station and interacting with IVA interfaces. IVA crew will locally supervise the robot using the same scripts and also teleoperate the robot to simulate scenarios with the robot working alone or as an assistant during space walks.