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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 667 records · Page 37
All sourcesNASA NTRSDOE OSTI
NASA NTRS2010

Aerothermal Protuberance Heating Design and Test Configurations for Ascent Vehicle Design

A series of tests were conducted to evaluate protuberance heating for the purposes of vehicle design and modification. These tests represent a state of the art approach to both testing and instrumentation for defining aerothermal protuberance effects on the protuberance and surrounding areas. The testing was performed with a number of wind tunnel entries beginning with the proof of concept "pathfinder" test in the Test Section 1 (TS1) tunnel in the Langley Unitary Plan Wind Tunnel (UPWT). The TS1 section (see Figures 1a and 1b) is a lower Mach number tunnel and the Test Section 2 (TS2) has overlapping and higher Mach number capability as showin in Figure 1c. The pathfinder concept was proven and testing proceeded for a series of protuberance tests using an existing splitter aluminum protuberance mounting plate, Macor protuberances, thin film gages, total temperature and pressure gages, Kulite pressure transducers, Infra-Red camera imaging, LASER velocimetry evaluations and the UPWT data collection system. A boundary layer rake was used to identify the boundary layer profile at the protuberance locations for testing and helped protuberance design. This paper discusses the techniques and instrumentation used during the protuberance heating tests performed in the UPWT in TS1 and TS2. Runs of the protuberances were made Mach numbers of 1.5, 2.16, 2.65, and 3.51. The data set generated from this testing is for ascent protuberance effects and is termed Protuberance Heating Ascent Data (PHAD) and this testing may be termed PHAD-1 to distinguish it from future testing of this type.

Martin, Charles E.↗
NASA NTRS2004

Zeolite Formation and Weathering Processes in Dry Valleys of Antartica: Martian Analogs

Terrestrial weathering processes in cold-desert climates such as the Dry Valleys of Antarctica may provide an excellent analog to chemical weathering and diagenesis of soils on Mars. Detailed studies of soil development and the chemical and mineralogical alterations occurring within soil columns in Wright Valley, Antarctica show incredible complexity in the upper meter of soil. Previous workers noted the ice-free Dry Valleys are the best terrestrial approximations to contemporary Mars. Images returned from the Pathfinder and Spirit landers show similarities to surfaces observed within the Dry Valleys. Similarities to Mars that exist in these valleys are: mean temperatures always below freezing (-20 C), no rainfall, sparse snowfall-rapidly removed by sublimation, desiccating winds, diurnal freeze-thaw cycles (even during daylight hours), low humidity, oxidative environment, relatively high solar radiation and low magnetic fields . The Dry Valley soils contain irregular distributions and low abundances of soil microorganisms that are somewhat unusual on Earth. Physical processes-such as sand abrasion-are dominant mechanisms of rock weathering in Antarctica. However, chemical weathering is also an important process even in such extreme climates. For example, ionic migration occurs even in frozen soils along liquid films on individual soil particles. It has also been shown that water with liquid-like properties is present in soils at temperatures on the order of approx.-80 C and it has been observed that the percentage of oxidized iron increases with increasing soil age and enrichments in oxidized iron occurs toward the surface. The presence of evaporates is evident and appear similar to "evaporite sites" within the Pathfinder and Spirit sites. Evaporites indicate ionic migration and chemical activity even in the permanently frozen zone. The presence of evaporates indicates that chemical weathering of rocks and possibly soils has been active. Authogenic zeolites have been identified within the soil columns because they are fragile; i.e. they are euhedral, unabraded, and unfractured, strongly suggesting in situ formation. Their presence in Antarctic samples is another indication that diagenic processes are active in cold-desert environments. The presence of zeolites, and other clays along with halites, sulfates, carbonates, and hydrates are to be expected within the soil columns on Mars at the Gusev and Isidis Planitia regions. The presence of such water-bearing minerals beneath the surface supplies one of the requirements to support biological activity on Mars.

Gibson, E. K., Jr.↗
NASA NTRS2007

Space Technology 7 : Micropropulsion and Mass Distribution

The NASA New Millennium Program Space Technology 7 (ST7) project will validate technology for precision spacecraft control. The ST7 disturbance reduction system (DRS) will contain new micropropulsion technology to be flown as part of the European Space Agency's LISA (laser interferometer space antenna) Pathfinder project. After launch into a low Earth orbit in early 2010, the LISA Pathfinder spacecraft will be maneuvered to a halo orbit about the Earth-Sun LI Lagrange point for operations. The DRS will control the position of the spacecraft relative to a reference to an accuracy of one nanometer over time scales of several thousand seconds. To perform the control the spacecraft will use a new colloid thruster technology. The thrusters will operate over the range of 5 to 30 micro-Newtons with precision of 0.1 micro-Newton. The thrust will be generated by using a high electric field to extract charged droplets of a conducting colloid fluid and accelerating them with a precisely adjustable voltage. The control position reference will be provided by the European LISA Technology Package, which will include two nearly free-floating test masses. The test mass position and attitude will be sensed and adjusted using electrostatic capacitance bridges. The DRS will control the spacecraft position with respect to one test mass while minimizing disturbances on the second test mass. The dynamic control system will cover eighteen degrees of freedom, six for each of the test masses and six for the spacecraft. In the absence of other disturbances, the test masses will slowly gravitate toward local concentrations of spacecraft mass. The test mass acceleration must be minimized to maintain the acceleration of the enclosing drag-free spacecraft within the control authority of the micropropulsion system. Therefore, test mass acceleration must be predicted by accurate measurement of mass distribution, then offset by the placement of specially shaped balance masses near each test mass. The - acceleration is characterized by calculating the gravitational effect of over ten million modeled points of a nearly 500-kg spacecraft. This paper provides an overview of the mission technology and the process of precision mass modeling of the DRS equipment.

ST-7↗
NASA NTRS2004

Electrodynamic Dust Shield for Solar Panels on Mars

The Materials Adherence Experiment on the Mars Pathfinder mission measured an obscuration of the solar arrays due to dust deposition at a rate of about 0.2 8% per day. It was estimated that settling dust may cause degradation in performance of a solar panel of between 22% and 89% over the course of two years [1, 2]. These results were obtained without the presence of a global dust storm. Several types of adherence forces keep dust particles attached to surfaces. The most widely discussed adherence force is the electrostatic force. Laboratory experiments [3] as well as indirect evidence from the Wheel Abrasion Experiment on Pathfinder [4] indicate that it is very likely that the particles suspended in the Martian atmosphere are electrostatically charged.

Calle, C. I.↗
NASA NTRS2014

Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development and Performance Analysis

The Space Launch System (SLS) base heating test is broken down into two test programs: (1) Pathfinder and (2) Main Test. The Pathfinder Test Program focuses on the design, development, hot-fire test and performance analyses of the 2% sub-scale SLS core-stage and booster element propulsion systems. The core-stage propulsion system is composed of four gaseous oxygen/hydrogen RS-25D model engines and the booster element is composed of two aluminum-based model solid rocket motors (SRMs). The first section of the paper discusses the motivation and test facility specifications for the test program. The second section briefly investigates the internal flow path of the design. The third section briefly shows the performance of the model RS-25D engines and SRMs for the conducted short duration hot-fire tests. Good agreement is observed based on design prediction analysis and test data. This program is a challenging research and development effort that has not been attempted in 40+ years for a NASA vehicle.

Mehta, Manish↗
NASA NTRS2014

Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development & Performance Analysis

ATA-002 Technical Team has successfully designed, developed, tested and assessed the SLS Pathfinder propulsion systems for the Main Base Heating Test Program. Major Outcomes of the Pathfinder Test Program: Reach 90% of full-scale chamber pressure Achieved all engine/motor design parameter requirements Reach steady plume flow behavior in less than 35 msec Steady chamber pressure for 60 to 100 msec during engine/motor operation Similar model engine/motor performance to full-scale SLS system Mitigated nozzle throat and combustor thermal erosion Test data shows good agreement with numerical prediction codes Next phase of the ATA-002 Test Program Design & development of the SLS OML for the Main Base Heating Test Tweak BSRM design to optimize performance Tweak CS-REM design to increase robustness MSFC Aerosciences and CUBRC have the capability to develop sub-scale propulsion systems to meet desired performance requirements for short-duration testing.

Mehta, Manish↗
NASA NTRS2013

V and V of Lexical, Syntactic and Semantic Properties for Interactive Systems Through Model Checking of Formal Description of Dialog

During early phases of the development of an interactive system, future system properties are identified (through interaction with end users in the brainstorming and prototyping phase of the application, or by other stakehold-ers) imposing requirements on the final system. They can be specific to the application under development or generic to all applications such as usability principles. Instances of specific properties include visibility of the aircraft altitude, speed… in the cockpit and the continuous possibility of disengaging the autopilot in whatever state the aircraft is. Instances of generic properties include availability of undo (for undoable functions) and availability of a progression bar for functions lasting more than four seconds. While behavioral models of interactive systems using formal description techniques provide complete and unambiguous descriptions of states and state changes, it does not provide explicit representation of the absence or presence of properties. Assessing that the system that has been built is the right system remains a challenge usually met through extensive use and acceptance tests. By the explicit representation of properties and the availability of tools to support checking these properties, it becomes possible to provide developers with means for systematic exploration of the behavioral models and assessment of the presence or absence of these properties. This paper proposes the synergistic use two tools for checking both generic and specific properties of interactive applications: Petshop and Java PathFinder. Petshop is dedicated to the description of interactive system behavior. Java PathFinder is dedicated to the runtime verification of Java applications and as an extension dedicated to User Interfaces. This approach is exemplified on a safety critical application in the area of interactive cockpits for large civil aircrafts.

human-computer interface↗
NASA NTRS2014

Quantifying the Amount of Ice in Cold Tropical Cirrus Clouds

How much ice is there in the Tropical Tropopause layer, globally? How does one begin to answer that question? Clouds are currently the largest source of uncertainty in climate models, and the ice water content (IWC) of cold cirrus clouds is needed to understand the total water and radiation budgets of the upper troposphere and lower stratosphere (UT/LS). The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite, originally a "pathfinder" mission only expected to last for three years, has now been operational for more than eight years. Lidar data from CALIPSO can provide information about how IWC is vertically distributed in the UT/LS, and about inter-annual variability and seasonal changes in cloud ice. However, cloud IWC is difficult to measure accurately with either remote or in situ instruments because IWC from cold cirrus clouds is derived from the particle cross-sectional area or visible extinction coefficient. Assumptions must be made about the relationship between the area, volume and density of ice particles with various crystal habits. Recently there have been numerous aircraft field campaigns providing detailed information about cirrus ice water content from cloud probes. This presentation evaluates the assumptions made when creating the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) global IWC data set, using recently reanalyzed aircraft particle probe measurements of very cold, thin TTL cirrus from the 2006 CR-AVE.

Avery, Melody A.↗
NASA NTRS2012

An Information NEXUS: The NASA Global Hawk Link Module

The Link Module described in this paper was first developed for the NASA Global Hawk Pacific Mission (GloPAC), four flights of 30 hour duration, supporting the Aura Validation Experiment (AVE). Its second use was during the Genesis and Rapid Intensification Processes (GRIP) experiment, a NASA Earth Science field experiment to better understand how tropical storms form and develop into major hurricanes. In these missions, the Link module negotiated all communication over the high bandwidth Ku satellite link, archived al the science data from onboard experiments in a spatially enable database, routed command and control of the instruments from the Global Hawk Operations Center, and retransmitted select data sets directly to experimenters control and analysis systems. The availability of aggregated information from collections of sensors, and remote control capabilities, in real-time, is revolutionizing the way Airborne Science is being conducted. Also described is the next generation Link Module now being designed and tested to support the NASA Earth Venture missions, the Hurricane and Severe Storm Sentinel (HS3) mission, and Airborne Tropical Tropopause Experiment (ATTREX) mission. Advanced data fusion technologies being developed will further advance the Scientific productivity, flexibility and robustness of these systems. Historically, the Link module evolved from the instrument and communication interface controller used by NASA's Pathfinder and Pathfinder plus solar powered UAS's in the late 1990's. It later was expanded for use in the AIRDAS four channel scanner flown on the NASA Altus UAS, and then again to a module in the AMS twelve channel multispectral scanner flying on the NASA (Predator-b) Ikhana UAS. The current system is the next step in the evolution, a multi board system packaged in a Curtiss Wright MIL-spec, flight qualified enclosure.

Remote Sensing↗
NASA NTRS2002

Cars on Mars

Mars is one of the most fascinating planets in the solar system, featuring an atmosphere, water, and enormous volcanoes and canyons. The Mars Pathfinder, Global Surveyor, and Odyssey missions mark the first wave of the Planet Earth's coming invasion of the red planet, changing our views of the past and future of the planet and the possibilities of life. Scientist and science-fiction writer Geoffrey A. Landis will present experiences on the Pathfinder mission, the challenges of using solar power on the surface of Mars, and present future missions to Mars such as the upcoming Mars Twin Rovers, which will launch two highly-capable vehicles in 2003 to explore the surface of Mars.

Landis, Geoffrey A.↗
NASA NTRS2008

Delivery of Colloid Micro-Newton Thrusters for the Space Technology 7 Mission

Two flight-qualified clusters of four Colloid Micro-Newton Thruster (CMNT) systems have been delivered to the Jet Propulsion Laboratory (JPL). The clusters will provide precise spacecraft control for the drag-free technology demonstration mission, Space Technology 7 (ST7). The ST7 mission is sponsored by the NASA New Millennium Program and will demonstrate precision formation flying technologies for future missions such as the Laser Interferometer Space Antenna (LISA) mission. The ST7 disturbance reduction system (DRS) will be on the ESA LISA Pathfinder spacecraft using the European gravitational reference sensor (GRS) as part of the ESA LISA Technology Package (LTP). Developed by Busek Co. Inc., with support from JPL in design and testing, the CMNT has been developed over the last six years into a flight-ready and flight-qualified microthruster system, the first of its kind. Recent flight-unit qualification tests have included vibration and thermal vacuum environmental testing, as well as performance verification and acceptance tests. All tests have been completed successfully prior to delivery to JPL. Delivery of the first flight unit occurred in February of 2008 with the second unit following in May of 2008. Since arrival at JPL, the units have successfully passed through mass distribution, magnetic, and EMI/EMC measurements and tests as part of the integration and test (I&T) activities including the integrated avionics unit (IAU). Flight software sequences have been tested and validated with the full flight DRS instrument successfully to the extent possible in ground testing, including full functional and 72 hour autonomous operations tests. Delivery of the cluster assemblies along with the IAU to ESA for integration into the LISA Pathfinder spacecraft is planned for the summer of 2008 with a planned launch and flight demonstration in late 2010.

Precision Formation Flying↗
NASA NTRS2015

The Role of the NASA Global Hawk Link Module as an Information Nexus For Atmospheric Mapping Missions

The Link Module described in this paper was developed for the NASA Uninhabited Aerial System (UAS) Global Hawk Pacific Mission (GloPAC) Airborne Science Campaign; four flights of 30 hour duration, supporting the Aura Validation Experiment (AVE). It was used again during the Genesis and Rapid Intensification Processes (GRIP) experiment, a NASA Earth Science field experiment to better understand how tropical storms form and develop into major hurricanes. In these missions, the Link Module negotiated all communication over the high bandwidth Ku satellite link, archived all the science data from onboard experiments in a spatially enabled database, routed command and control of the instruments from the Global Hawk Operations Center, and re-transmitted select data sets directly to experimenters control and analysis systems. The availability of aggregated information from collections of sensors, and remote control capabilities, in real-time, is revolutionizing the way Airborne Science is being conducted. The Link Module NG now being flown in support of the NASA Earth Venture missions, the Hurricane and Severe Storm Sentinel (HS3) mission, and Airborne Tropical Tropopause Experiment (A TTREX) mission, has advanced data fusion technologies that are further advancing the Scientific productivity, flexibility and robustness of these systems. On-the-fly traffic shaping has been developed to allow the high definition video, used for critical flight control segments, to dynamically allocate variable bandwidth on demand. Historically, the Link Module evolved from the instrument and communication interface controller used by NASA's Pathfinder and Pathfinder plus solar powered UAS's in the late 1990' s. It later was expanded for use in the AIRDAS four channel scanner flown on the NASA Altus UAS, and then again to a module in the AMS twelve channel multispectral scanner flying on the NASA (Predator-b) Ikhana UAS. The current system is the answer to the challenges imposed by extremely long duration UASs, with on-board multi-instrument (>= 12) Sensor Webs.

Hurricanes↗
NASA NTRS2016

NASA's Earth Science Flight Program Meets the Challenges of Today and Tomorrow

NASA's Earth science flight program is a dynamic undertaking that consists of a large fleet of operating satellites, an array of satellite and instrument projects in various stages of development, a robust airborne science program, and a massive data archiving and distribution system. Each element of the flight program is complex and present unique challenges. NASA builds upon its successes and learns from its setbacks to manage this evolving portfolio to meet NASA's Earth science objectives. NASA fleet of 16 operating missions provide a wide range of scientific measurements made from dedicated Earth science satellites and from instruments mounted to the International Space Station. For operational missions, the program must address issues such as an aging satellites operating well beyond their prime mission, constellation flying, and collision avoidance with other spacecraft and orbital debris. Projects in development are divided into two broad categories: systematic missions and pathfinders. The Earth Systematic Missions (ESM) include a broad range of multi-disciplinary Earth-observing research satellite missions aimed at understanding the Earth system and its response to natural and human-induced forces and changes. Understanding these forces will help determine how to predict future changes, and how to mitigate or adapt to these changes. The Earth System Science Pathfinder (ESSP) program provides frequent, regular, competitively selected Earth science research opportunities that accommodate new and emerging scientific priorities and measurement capabilities. This results in a series of relatively low-cost, small-sized investigations and missions. Principal investigators whose scientific objectives support a variety of studies lead these missions, including studies of the atmosphere, oceans, land surface, polar ice regions, or solid Earth. This portfolio of missions and investigations provides opportunity for investment in innovative Earth science that enhances NASA's capability for better understanding the current state of the Earth system. ESM and ESSP projects often involve partnerships with other US agencies and/or international organizations. This adds to the complexity of mission development, but allows for a greater scientific return on NASA's investments. The Earth Science Airborne Science Program provides manned and unmanned aircraft systems that further science and advance the use of satellite data. NASA uses these assets worldwide in campaigns to investigate extreme weather events, observe Earth system processes, obtain data for Earth science modeling activities, and calibrate instruments flying aboard Earth science spacecraft. The Airborne Science Program has six dedicated aircraft and access to many other platforms. The Earth Science Multi-Mission Operations program acquires, preserves, and distributes observational data from operating spacecraft to support Earth Science research focus areas. The Earth Observing System Data and Information System (EOSDIS), which has been in operations since 1994, primarily accomplishes this. EOSDIS acquires, processes, archives, and distributes Earth Science data and information products. The archiving of NASA Earth Science information happens at eight Distributed Active Archive Centers (DAACs) and four disciplinary data centers located across the United States. The DAACs specialize by topic area, and make their data available to researchers around the world. The DAACs currently house over 9 petabytes of data, growing at a rate of 6.4 terabytes per day. NASA's current Earth Science portfolio is responsive to the National Research Council (NRC) 2007 Earth Science Decadal Survey and well as the 2010 NASA Response to President Obama's Climate Plan. As the program evolves into the future it will leverage the lessons learned from the current missions in operations and development, and plan for adjustments to future objectives in response to the anticipated 2017 NRC Decadal Survey.

Flight Program↗
NASA NTRS2014

Optimal Design of Calibration Signals in Space Borne Gravitational Wave Detectors

Future space borne gravitational wave detectors will require a precise definition of calibration signals to ensure the achievement of their design sensitivity. The careful design of the test signals plays a key role in the correct understanding and characterization of these instruments. In that sense, methods achieving optimal experiment designs must be considered as complementary to the parameter estimation methods being used to determine the parameters describing the system. The relevance of experiment design is particularly significant for the LISA Pathfinder mission, which will spend most of its operation time performing experiments to characterize key technologies for future space borne gravitational wave observatories. Here we propose a framework to derive the optimal signals in terms of minimum parameter uncertainty to be injected to these instruments during its calibration phase. We compare our results with an alternative numerical algorithm which achieves an optimal input signal by iteratively improving an initial guess. We show agreement of both approaches when applied to the LISA Pathfinder case.

LISA Path_nder mission↗
NASA NTRS2015

Hypersonic Inflatable Aerodynamic Decelerator Ground Test Development

Hypersonic Inflatable Aerodynamic Decelerator (HIAD) technology readiness levels have been incrementally matured by NASA over the last thirteen years, with most recent support from NASA's Space Technology Mission Directorate (STMD) Game Changing Development Program (GCDP). Recently STMD GCDP has authorized funding and support through fiscal year 2015 (FY15) for continued HIAD ground developments which support a Mars Entry, Descent, and Landing (EDL) study. The Mars study will assess the viability of various EDL architectures to enable a Mars human architecture pathfinder mission planned for mid-2020. At its conclusion in November 2014, NASA's first HIAD ground development effort had demonstrated success with fabricating a 50 W/cm2 modular thermal protection system, a 400 C capable inflatable structure, a 10-meter scale aeroshell manufacturing capability, together with calibrated thermal and structural models. Despite the unquestionable success of the first HIAD ground development effort, it was recognized that additional investment was needed in order to realize the full potential of the HIAD technology capability to enable future flight opportunities. The second HIAD ground development effort will focus on extending performance capability in key technology areas that include thermal protection system, lifting-body structures, inflation systems, flight control, stage transitions, and 15-meter aeroshell scalability. This paper presents an overview of the accomplishments under the baseline HIAD development effort and current plans for a follow-on development effort focused on extending those critical technologies needed to enable a Mars Pathfinder mission.

Del Corso, Jospeh A.↗
NASA NTRS2016

Successful Completion of the JWST OGSE2 Cryogenic Test at JSC Chamber-A While Managing Numerous Challenges

The James Webb Space Telescope (JWST) Optical Telescope Element (OTE) assembly is the largest optically stable infrared-optimized telescope currently being manufactured and assembled, and scheduled for launch in 2018. The JWST OTE, including the primary mirrors, secondary mirror, and the Aft Optics Subsystems (AOS) are designed to be passively cooled and operate at near 45 degrees Kelvin. Due to the size of its large sunshield in relation to existing test facilities, JWST cannot be optically or thermally tested as a complete observatory-level system at flight temperatures. As a result, the telescope portion along with its instrument complement will be tested as a single unit very late in the program, and on the program schedule critical path. To mitigate schedule risks, a set of 'pathfinder' cryogenic tests will be performed to reduce program risks by demonstrating the optical testing capabilities of the facility, characterizing telescope thermal performance, and allowing project personnel to learn valuable testing lessons off-line. This paper describes the 'pathfinder' cryogenic test program, focusing on the recently completed second test in the series called the Optical Ground Support Equipment 2 (OGSE2) test. The JWST OGSE2 was successfully completed within the allocated project schedule while faced with numerous conflicting thermal requirements during cool-down to the final cryogenic operational temperatures, and during warm-up after the cryo-stable optical tests. The challenges include developing a pre-test cool-down and warm-up profiles without a reliable method to predict the thermal behaviors in a rarified helium environment, and managing the test article hardware safety driven by the project Limits and Constraints (L&C's). Furthermore, OGSE2 test included the time critical Aft Optics Subsystem (AOS), a part of the flight Optical Telescope Element that would need to be placed back in the overall telescope assembly integrations. The OGSE2 test requirements included the strict adherence of the project contamination controls due to the presence of the contamination sensitive flight optical elements. The test operations required close coordination of numerous personnel while they being exposed and trained for the 'final' combined OTE and instrument cryo-test in 2017. This paper will also encompass the OGSE2 thermal data look-back review.

JWST OGSE2 Cryogenic Test↗
NASA NTRS2016

The Segmented Aperture Interferometric Nulling Testbed (SAINT) I: Overview and Air-side System Description

This work presents an overview of the This work presents an overview of the Segmented Aperture Interferometric Nulling Testbed (SAINT), a project that will pair an actively-controlled macro-scale segmented mirror with the Visible Nulling Coronagraph (VNC). SAINT will incorporate the VNCs demonstrated wavefront sensing and control system to refine and quantify the end-to-end system performance for high-contrast starlight suppression. This pathfinder system will be used as a tool to study and refine approaches to mitigating instabilities and complex diffraction expected from future large segmented aperture telescopes., a project that will pair an actively-controlled macro-scale segmented mirror with the Visible Nulling Coronagraph (VNC). SAINT will incorporate the VNCs demonstrated wavefront sensing and control system to refine and quantify the end-to-end system performance for high-contrast starlight suppression. This pathfinder system will be used as a tool to study and refine approaches to mitigating instabilities and complex diffraction expected from future large segmented aperture telescopes.

wavefront sensing↗
NASA NTRS2017

Testing and Modeling of the Mars Atmospheric Processing Module

Here we report further progress in the development of the MARCO POLO-Mars Pathfinder Atmospheric Processing Module (APM). The APM is designed to demonstrate in situ resource utilization (ISRU) of the Martian atmosphere, which primarily consists of carbon dioxide (CO2). The APM is part of a larger project with the overall goal of collecting and utilizing CO2 found in the atmosphere and water in the regolith of Mars to produce methane and oxygen to be used as rocket propellant, eliminating the need to import those to Mars for human missions, thus significantly reducing costs. The initial focus of NASA's new ISRU Project is modeling of key ISRU components, such as the CO2 Freezers and the Sabatier reactor of the APM. We have designed models of those components and verified the models with the APM by gathering additional data for the Sabatier reactor. Future efforts will be focused on simultaneous operations of the APM and other MARCO POLO-Mars Pathfinder modules.

propellant production↗