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In support of the Constellation Program, NASA conducted an analysis of crew clothing and laundry options. Disposable clothing is currently used in human space missions. However, the new mission duration, goals, launch penalties and habitat environments may lead to a different conclusion. Mass and volume for disposable clothing are major penalties in long-duration human missions. Equivalent System Mass (ESM) of crew clothing and hygiene towels was estimated at about 11% of total life support system ESM for a 4-crew, 10-year Lunar Outpost mission. Ways to lessen this penalty include: reduce clothing supply mass through using clothes made of advanced fabrics, reduce daily usage rate by extending wear duration and employing a laundry with reusable clothing. Lunar habitat atmosphere pressure and therefore oxygen volume percentage will be different from Space Station or Shuttle. Thus flammability of clothing must be revisited.

Future manned habitats for a Lunar outpost or Martian base will require increased levels of self-sufficiency over Space Station Freedom to reduce the high costs and complexities of resupplying expendables, such as food for the crew. By growing food at these remote sites, not only will self-sufficiency be greatly increased, but significant benefits for crew life support will also be realized. Higher plants, such as those grown typically for food, are capable of consuming carbon dioxide (CO2), producing oxygen (O2), and reclaiming water (H2O) via transpiration. At NASA's Johnson Space Center (JSC) in Houston, Texas, the Regenerative Life Support Systems (RLSS) Test Bed project will use higher plants grown in a closed, controlled environment in conjunction with physicochemically-based life support systems to create an integrated biological/physicochemical RLSS.

In preparation for the contract award of the Crew Exploration Vehicle (CEV), the National Aeronautics and Space Administration (NASA) produced two design reference missions for the vehicle. The design references used teams of engineers across the agency to come up with two configurations. This process helped NASA understand the conflicts and limitations in the CEV design, and investigate options to solve them.

An energy balance was performed on the life support equipment used during the Phase III, 90-day, human Lunar-Mars Life Support Test Project at the Johnson Space Center. The purpose of the analysis was to account for all the energy sources, uses, and losses in the test-bed. Knowledge from this task may allow more energy efficient designs to be developed. Control volumes were defined and energy balance equations were generated for major systems. The analyses succeeded in balancing the energy fairly well for several systems. Further, the data showed that inefficiencies existed, and means of design optimization were subsequently suggested.

Exploration Life Support (ELS) is a technology development project under the National Aeronautics and Space Administration's (NASA) Exploration Technology Development Program. The ELS Project's goal is to develop and mature a suite of Environmental Control and Life Support System (ECLSS) technologies for potential use on human spacecraft under development in support of U.S. Space Exploration Policy. Technology development is directed at three major vehicle projects within NASA's Constellation Program: the Orion Crew Exploration Vehicle (CEV), the Altair Lunar Lander and Lunar Surface Systems, including habitats and pressurized rovers. The ELS Project includes four technical elements: Atmosphere Revitalization Systems, Water Recovery Systems, Waste Management Systems and Habitation Engineering, and two cross cutting elements, Systems Integration, Modeling and Analysis, and Validation and Testing.

With the Preliminary Design Review (PDR) for the Orion Crew Exploration Vehicle planned to be completed in 2009, Exploration Life Support (ELS), a technology development project under the National Aeronautics and Space Administration's (NASA) Exploration Technology Development Program, is focusing its efforts on needs for human lunar missions. The ELS Project's goal is to develop and mature a suite of Environmental Control and Life Support System (ECLSS) technologies for potential use on human spacecraft under development in support of U.S. Space Exploration Policy. ELS technology development is directed at three major vehicle projects within NASA's Constellation Program (CxP): the Orion Crew Exploration Vehicle (CEV), the Altair Lunar Lander and Lunar Surface Systems, including habitats and pressurized rovers.

The On-line Project Information System (OPIS) is the Exploration Life Support (ELS) mechanism for task data sharing and annual reporting. Fiscal year 2008 (FY08) was the first year in which ELS Principal Investigators (PI's) were required to complete an OPIS annual report. The reporting process consists of downloading a template that is customized to the task deliverable type(s), completing the report, and uploading the document to OPIS for review and approval. In addition to providing a general status and overview of OPIS features, this paper describes the user critiques and resulting system modifications of the first year of OPIS reporting efforts. Specifically, this paper discusses process communication and logistics issues, user interface ambiguity, report completion challenges, and the resultant or pending system improvements designed to circumvent such issues for the fiscal year 2009 reporting effort.

The amount of oxygen consumption for crew extravehicular activity (EVA) in future lunar exploration missions will be significant. Eight technologies to provide high pressure EVA O2 were investigated. They are: high pressure O2 storage, liquid oxygen (LOX) storage followed by vaporization, scavenging LOX from Lander followed by vaporization, LOX delivery followed by sorption compression, water electrolysis followed by compression, stand-alone high pressure water electrolyzer, Environmental Control and Life Support System (ECLSS) and Power Elements sharing a high pressure water electrolyzer, and ECLSS and In-Situ Resource Utilization (ISRU) Elements sharing a high pressure electrolyzer. A trade analysis was conducted comparing launch mass and equivalent system mass (ESM) of the eight technologies in open and closed ECLSS architectures. Technologies considered appropriate for the two architectures were selected and suggested for development.

Engineers at the Johnson Space Center (JSC) are using innovative strategies to design the TCS for the Bio-regenerative Planetary Life Support Systems Test Complex (BIO-Plex), a regenerative advanced life support system ground test bed. This paper provides a current description of the BIO-Plex TCS design, testing objectives, analyses, descriptions of the TCS test articles expected to be tested in the BIO-Plex, and forward work regarding TCS. The TCS has been divided into some subsystems identified as permanent “infrastructure” for the BIO-Plex and others that are “test articles” that may change from one test to the next. The infrastructure subsystems are the Heating, Ventilation and Air-Conditioning (HVAC), the Crew Chambers Internal Thermal Control Subsystem (CC ITCS), the Biomass Production Chamber Internal Thermal Control Subsystem (BPC ITCS), the Waste Heat Distribution Subsystem (WHDS) and the External Thermal Control Subsystem (ETCS).

The development of an optimum regenerative Advanced Life Support (ALS) system for future Mars missions has been a crucial issue in the space industry. Considering the numerous potential technologies for subsystems with the complexity of the Air Revitalization System (ARS), Water Reclamation System (WRS), and Waste Management System of the Environmental Control and Life Support System (ECLSS), it will be time-consuming and costly to determine the best combination of these technologies without a powerful sizing analysis tool. Johnson Space Center (JSC), therefore, initiated the development of ALSSAT using Microsoft® Excel for this purpose. ALSSAT has been developed based upon the ALS Requirement and Design Definition Document (Ref. 18). In 1999, a paper describing the development of ALSSAT with its built-in ARS mass balance model (Ref. 21) was published in ICES.

The Systems Integration, Modeling and Analysis (SIMA) element1 of the National Aeronautics and Space Administration (NASA) Advanced Life Support (ALS) Project conducts on-going studies to determine the most efficient means of achieving a human mission to Mars. Life support for the astronauts constitutes an extremely important part of the mission and will undoubtedly add significant mass, power, volume, cooling and crew time requirements to the mission. Equivalent system mass (ESM) is the sum of these five parameters on an equivalent mass basis and can be used to identify potential ways to reduce the overall cost of the mission. SIMA has documented several reference missions in enough detail to allow quantitative studies to identify optimum ALS architectures. The Mars Dual Lander Mission, under consideration by the Johnson Space Center (JSC) Exploration Office, is one of those missions.

This paper builds on a steady-state investigation of waste heat reuse in an Advanced Life Support System (ALSS) for a Mars mission with a low degree of crop growth. In past studies, such a system has been defined in terms of technology types, hot and cold stream identification and stream energy content. The maximum steady-state potential for power and cooling savings within the system was computed via the Pinch Method. In this paper, the next step is taken toward achieving a pragmatic estimate of costs and savings associated with waste heat reuse in terms of equivalent system mass (ESM). In this paper, the assumption of steady-state flows are discarded, and a proposed schedule is developed for activities that are of interest in terms of waste heat reuse. The advanced life support system for the Mars Dual Lander Transit Vehicle is the system of interest.

To effectively develop advanced life support technologies to support humans on future missions into space, the requirements for these missions must first be defined. How many people will go? Where will they go? What risks must be protected against? Since NASA does not officially establish new exploration programs until authorized by Congress, there are no program requirements documents or list of “planned missions” to refer to. Therefore, technology developers must look elsewhere for information on how and where their development efforts and concepts may be used. This paper summarizes the development of several sources designed to help Advanced Life Support researchers working to extend a human presence in space.

Solid Waste Management (SWM) systems of current and previous space flight missions have employed relatively uncomplicated methods of waste collection, storage and return to Earth. NASA's long-term objectives, however, will likely include human-rated missions that are longer in both duration and distance, with little to no opportunity for re-supply. Such missions will likely exert increased demands upon all sub-systems, particularly the SWM system. In order to provide guidance to SWM Research and Technology Development (R&TD) efforts and overall system development, the establishment of appropriate SWM system requirements is necessary. Because future long duration missions are not yet fully defined, thorough mission-specific requirements have not yet been drafted.

Long duration missions pose substantial new challenges for solid waste management in Advanced Life Support (ALS) systems. These possibly include storing large volumes of waste material in a safe manner, rendering wastes stable or sterilized for extended periods of time, and/or processing wastes for recovery of vital resources. This is further complicated because future missions remain ill-defined with respect to waste stream quantity, composition and generation schedule. Without definitive knowledge of this information, development of mission requirements is hampered. Additionally, even if waste streams were well characterized, other operational and processing needs require clarification (e.g. resource recovery requirements and planetary protection constraints). Therefore, the development of solid waste management (SWM) subsystem requirements for long duration space missions is an inherently uncertain, complex and iterative process.

The On-line Project Information System (OPIS) is a LAMP-based (Linux, Apache, MySQL, PHP) system being developed at NASA Ames Research Center to improve Agency information transfer and data availability, largely for improvement of system analysis and engineering. The tool will enable users to investigate NASA technology development efforts, connect with experts, and access technology development data. OPIS is currently being developed for NASA's Exploration Life Support (ELS) Project. Within OPIS, NASA ELS Managers assign projects to Principal Investigators (PI), track responsible individuals and institutions, and designate reporting assignments. Each PI populates a “Project Page” with a project overview, team member information, files, citations, and images. PI's may also delegate on-line report viewing and editing privileges to specific team members. Users can browse or search for project and member information.

When permanent bases are established on the moon, various methods may be employed to reject the heat generated by the base. One proposed concept is the use of a heat pump operating with a vertical, flow-through thermal radiator which is mounted on a Space Station type habitation module. Since the temperature of the lunar surface varies over the lunar day, the sink temperature for heat pump heat rejection will vary. As a result, the heat pump power demand will also vary over the lunar day. This variable power requirement could be provided by a fixed horizontal solar photovoltaic (PV) array placed on the lunar surface, since its power production will vary sinusoidally with the time of day. Using a dedicated PV array to power the heat pump may represent a favorable mass trade-off compared to enlarging the size of the base's central power grid due to power system simplification and improvements in efficiency.

In an era of tight fiscal constraints, research and development funds are not sufficient to study all possible avenues for technology development. Hence, development priorities must be set and funding decisions made based on the projected benefits which will arise from fully developing different technologies. In order to identify promising development initiatives for advanced thermal control systems, a study was conducted which quantified the potential mass savings of various technologies. Assessments were made for five reference missions considered to be likely candidates for major human space flight initiatives beyond the International Space Station. The reference missions considered were Space Station Evolution, Space Shuttle Replacement, First Lunar Outpost Lander, Permanent Lunar Base, and Mars Lander. For each mission a baseline active thermal control system was defined and mass estimates were established.

Newly outlined missions in the Vision for U.S. Space Exploration include extended human habitation on Mars. During these missions, large amounts of waste materials will be generated in solid, liquid and gaseous form. Returning these wastes to Earth will be extremely costly, and increase the opportunity for back contamination. Therefore, it is advantageous to investigate the potential for wastes to remain on Mars after mission completion. Untreated, these wastes are a reservoir of live/dead organisms and molecules considered “biomarkers” (i.e., indicators of life). If released to the planetary surface, these materials can potentially interfere with exobiology studies, disrupt any existent martian ecology and pose human safety concerns. Waste Management (WM) systems must therefore be specifically designed to control release of problematic materials both during the active phase of the mission, and for any specified post-mission duration.

The development of the Advanced Life Support (ALS) Sizing Analysis Tool (ALSSAT) using Microsoft® Excel was initiated by the Crew and Thermal Systems Division (CTSD) of Johnson Space Center (JSC) in 1997 to support the ALS and Exploration Offices in Environmental Control and Life Support System (ECLSS) design and studies. It aids the user in performing detailed sizing of the ECLSS for different combinations of the ALS regenerative system technologies (1, 2). This analysis tool will assist the user in performing ECLSS preliminary design and trade studies as well as system optimization efficiently and economically.