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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 379 records · Page 21

Advanced Life Support Technologies and Scenarios

As NASA looks beyond the International Space Station toward long-duration, deep space missions away from Earth, the current practice of supplying consumables and spares will not be practical nor affordable. New approaches are sought for life support and habitation systems that will reduce dependency on Earth and increase mission sustainability. To reduce launch mass, further closure of Environmental Control and Life Support Systems (ECLSS) beyond the current capability of the ISS will be required. Areas of particular interest include achieving higher degrees of recycling within Atmosphere Revitalization, Water Recovery and Waste Management Systems. NASA is currently investigating advanced carbon dioxide reduction processes that surpass the level of oxygen recovery available from the Sabatier Carbon Dioxide Reduction Assembly (CRA) on the ISS. Improving the efficiency of the recovery of water from spacecraft solid and liquid wastes is possible through use of emerging technologies such as the heat melt compactor and brine dewatering systems. Another significant consumable is that of food. Food production systems based on higher plants may not only contribute significantly to the diet, but also contribute to atmosphere revitalization, water purification and waste utilization. Bioreactors may be potentially utilized for wastewater and solid waste management. The level at which bioregenerative technologies are utilized will depend on their comparative requirements for spacecraft resources including mass, power, volume, heat rejection, crew time and reliability. Planetary protection requirements will need to be considered for missions to other solar system bodies.

Barta, Daniel J.↗

NASA Human Spaceflight Scenarios - Do All Our Models Still Say 'No'?

We analyze the potential life cycle cost of assorted NASA human spaceflight architectures an architecture as a sum of individual systems, working together. With the prior questions of high costs, limited budgets and uncertainties in mind, public private partnerships are central in these architectures. The cost data for current commercial public private partnerships is encouraging, as are cost estimates for future partnership approaches beyond low Earth orbit.

cost modeling estimation↗

A Major Solar Eruptive Event in July 2012: Defining Extreme Space Weather Scenarios

A key goal for space weather studies is to define severe and extreme conditions that might plausibly afflict human technology. On 23 July 2012, solar active region 1520 (approx. 141 deg W heliographic longitude) gave rise to a powerful coronal mass ejection (CME) with an initial speed that was determined to be 2500+/-500 km/s. The eruption was directed away from Earth toward 125 deg W longitude. STEREO-A sensors detected the CME arrival only about 19 h later and made in situ measurements of the solar wind and interplanetary magnetic field. In this paper, we address the question of what would have happened if this powerful interplanetary event had been Earthward directed. Using a well-proven geomagnetic storm forecast model, we find that the 23-24 July event would certainly have produced a geomagnetic storm that was comparable to the largest events of the twentieth century (Dst approx. - 500 nT). Using plausible assumptions about seasonal and time-of-day orientation of the Earth's magnetic dipole, the most extreme modeled value of storm-time disturbance would have been Dst= - 1182 nT. This is considerably larger than estimates for the famous Carrington storm of 1859. This finding has far reaching implications because it demonstrates that extreme space weather conditions such as those during March of 1989 or September of 1859 can happen even during a modest solar activity cycle such as the one presently underway. We argue that this extreme event should immediately be employed by the space weather community to model severe space weather effects on technological systems such as the electric power grid.

solar longitude↗

Habitable Climate Scenarios for Proxima Centauri B with a Dynamic Ocean

The nearby exoplanet Proxima Centauri b will be a prime future target for characterization, despite questions about its retention of water. Climate models with static oceans suggest that Proxima b could harbor a small dayside surface ocean despite its weak instellation. We present the first climate simulations of Proxima b with a dynamic ocean. We find that an ocean-covered Proxima b could have a much broader area of surface liquid water but at much colder temperatures than previously suggested, due to ocean heat transport and/or depression of the freezing point by salinity. Elevated greenhouse gas concentrations do not necessarily produce more open ocean because of dynamic regime transitions between a state with an equatorial Rossby-Kelvin wave pattern and a state with a day-night circulation. For an evolutionary path leading to a highly saline ocean, Proxima b could be an inhabited, mostly open ocean planet with halophilic life. A fresh water ocean produces a smaller liquid region than does an Earth salinity ocean. An ocean planet in 3:2 spin-orbit resonance has a permanent tropical waterbelt for moderate eccentricity. A larger vs. smaller area of surface liquid water for similar equilibrium temperature may be distinguishable using the amplitude of the thermal phase curve. Simulations of Proxima Centauri b may be a model for the habitability of weakly irradiated planets orbiting slightly cooler or warmer stars, e.g., in the TRAPPIST-1, LHS 1140, GJ 273, and GJ 3293 systems.

Aquaplanet↗

Developing the “Lunar Vicinity” Scenario of the Global Exploration Roadmap

The Global Exploration Roadmap (GER) has been developed by the International Space Exploration Coordination Group (ISECG – comprised of 14 space agencies) to define various pathways to getting humans beyond low Earth orbit and eventually to Mars. Such pathways include visiting asteroids or the Moon before going on to Mars. This document has been written at a very high level and many details are still to be determined. However, a number of important papers regarding international space exploration can form a basis for this document.

Global↗

An Autonomous sUAS Operating in UTM TCL4+ and STEReO Fire Scenario

This study presents a sUAS payload point design that enables autonomous BVLOS flightin UTM TCL4+ urban environments and STEReO fire responses. The payload components include an onboard computer, 360 deg LIDAR, range finder altimeter, downward-facing monocular camera, forward-facing thermal and visible light dual camera, vehicle-to-vehicle radio modem, and Li-ion smart battery. The components are mounted on an enclosed structural frame that was designed in-house. Placing the autonomy components onboard leverages the advantages of sUAS over manned aircraft such as low-cost, quick response time, and increased scalability. Autonomous capabilities include object and fire detection, V2V communication, embedded processing, and SLAM. Data processing is conducted on-board the aircraft to eliminate the dependency on a ground station downlink. The payload is evaluated in both software simulation as well as flight tests.

Autonomous UAS↗