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NASA NTRSDate not supplied

Modular Assembled Radiators for Nuclear Electric Propulsion (NEP) VehicLes (MARVL) Project Thermal Technology Development

Nuclear Electric Propulsion (NEP) has been considered for crew and cargo class missions to Mars for more than six decades. The Primary Heat Rejection Subsystem (PHRS) of an NEP vehicle expels the megawatts of waste heat generated by the Power Conversion Subsystem (PCS). In previous studies, integrating the majority of the NEP vehicle within a single launch fairing required the use of complex deployable elements and resulted in reduced PCS efficiency. To achieve the necessary radiating area, past design studies have utilized massive multi-wing folding radiators resulting in conceptual PHRS designs that have been widely acknowledged as non-optimal. The Modular Assembled Radiators for NEP VehicLes (MARVL) project is incorporating in-Space Assembly (iSA) into the design process to realize lightweight, modular, and more capable PHRS radiators. Since the project’s Authority to Proceed (ATP) date of October 2024, the project team has been developing a modular design for the PHRS radiators that will be suitable for both the Mars mission environments and iSA commissioning operations. This document captures the current progress of the incremental technology development for the thermal components of the MARVL System of Interest (SOI).

Modular Radiator↗

NASA NTRS2004

Identifying Organic Molecules in Space: The AstroBiology Explorer (ABE) Mission Concept

The AstroBiology Explorer (ABE) mission concept consists of a modest dedicated space observatory having a 60 cm class primary mirror cooled to T less than 50 K equipped with medium resolution cross-dispersed spectrometers having cooled large format near- and mid-infrared detector arrays. Such a system would be capable of addressing outstanding problems in Astrochemistry and Astrophysics that are particularly relevant to Astrobiology and addressable via astronomical observation. The mission's observaticxiai program woiild make fundamental scieztific: prngress in establishing the nature, distribution, formation and evolution of organic and other molecular materials in the following extra-terrestrial environments: 1) The Outflow of Dying Stars; 2) The Diffuse Interstellar Medium (DISM); 3) Dense Molecular Clouds, Star Formation Regions, and Young Stellar/Planetary Systems; 4) Planets, Satellites, and Small Bodies within the Solar System; and 5) The Interstellar Media of Other Galaxies ABE could make fundamental progress in all of these area by conducting a 1 to 2 year mission to obtain a coordinated set of infrared spectroscopic observations over the 2.5 - 20 micron spectral range at a spectral resolution of R greater than 2500 of about 1500 galaxies, stars, planetary nebulae, young stellar objects, and solar system objects.

Ennico, Kimberly↗

NASA NTRS2013

MESSENGER at Mercury: Early Orbital Operations

The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, launched in August 2004 under NASA's Discovery Program, was inserted into orbit about the planet Mercury in March 2011. MESSENGER's three flybys of Mercury in 2008-2009 marked the first spacecraft visits to the innermost planet since the Mariner 10 flybys in 1974-1975. The unprecedented orbital operations are yielding new insights into the nature and evolution of Mercury. The scientific questions that frame the MESSENGER mission led to the mission measurement objectives to be achieved by the seven payload instruments and the radio science experiment. Interweaving the full set of required orbital observations in a manner that maximizes the opportunity to satisfy all mission objectives and yet meet stringent spacecraft pointing and thermal constraints was a complex optimization problem that was solved with a software tool that simulates science observations and tracks progress toward meeting each objective. The final orbital observation plan, the outcome of that optimization process, meets all mission objectives. MESSENGER's Mercury Dual Imaging System is acquiring a global monochromatic image mosaic at better than 90% coverage and at least 250 m average resolution, a global color image mosaic at better than 90% coverage and at least 1 km average resolution, and global stereo imaging at better than 80% coverage and at least 250 m average resolution. Higher-resolution images are also being acquired of targeted areas. The elemental remote sensing instruments, including the Gamma-Ray and Neutron Spectrometer and the X-Ray Spectrometer, are being operated nearly continuously and will establish the average surface abundances of most major elements. The Visible and Infrared Spectrograph channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer is acquiring a global map of spectral reflectance from 300 to 1450 nm wavelength at a range of incidence and emission angles. Targeted areas have been selected for spectral coverage into the ultraviolet with the Ultraviolet and Visible Spectrometer (UVVS). MESSENGER's Mercury Laser Altimeter is acquiring topographic profiles when the slant range to Mercury's surface is less than 1800 km, encompassing latitudes from 20 deg. S to the north pole. Topography over the remainder of the southern hemisphere will be derived from stereo imaging, radio occultations, and limb profiles. MESSENGER's radio science experiment is determining Mercury's gravity field from Doppler signals acquired during frequent downlinks. MESSENGER's Magnetometer is measuring the vector magnetic field both within Mercury's magnetosphere and in Mercury's solar wind environment at an instrument sampling rate of up to 20 samples/s. The UVVS is determining the three-dimensional, time-dependent distribution of Mercury's exospheric neutral and ionic species via their emission lines. During each spacecraft orbit, the Energetic Particle Spectrometer measures energetic electrons and ions, and the Fast Imaging Plasma Spectrometer measures the energies and mass per charge of thermal plasma components, both within Mercury's magnetosphere and in Mercury's solar-wind environment. The primary mission observation sequence will continue for one Earth year, until March 2012. An extended mission, currently under discussion with NASA, would add a second year of orbital observations targeting a set of focused follow-on questions that build on observations to date and take advantage of the more active Sun expected during 2012-2013. MESSENGER's total primary mission cost, projected at $446 M in real-year dollars, is comparable to that of Mariner 10 after adjustment for inflation.

mercury↗

NASA NTRS2012

MESSENGER at Mercury: Early Orbital Operations

The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, launched in August 2004 under NASA's Discovery Program, was inserted into orbit about the planet Mercury in March 2011. MESSENGER's three flybys of Mercury in 2008-2009 marked the first spacecraft visits to the innermost planet since the Mariner 10 flybys in 1974-1975. The unprecedented orbital operations are yielding new insights into the nature and evolution of Mercury. The scientific questions that frame the MESSENGER mission led to the mission measurement objectives to be achieved by the seven payload instruments and the radio science experiment. Interweaving the full set of required orbital observations in a manner that maximizes the opportunity to satisfy all mission objectives and yet meet stringent spacecraft pointing and thermal constraints was a complex optimization problem that was solved with a software tool that simulates science observations and tracks progress toward meeting each objective. The final orbital observation plan, the outcome of that optimization process, meets all mission objectives. MESSENGER's Mercury Dual Imaging System is acquiring a global monochromatic image mosaic at better than 90%coverage and at least 250 m average resolution, a global color image mosaic at better than 90%coverage and at least 1 km average resolution, and global stereo imaging at better than 80%coverage and at least 250 m average resolution. Higher-resolution images are also being acquired of targeted areas. The elemental remote sensing instruments, including the Gamma-Ray and Neutron Spectrometer and the X-Ray Spectrometer, are being operated nearly continuously and will establish the average surface abundances of most major elements. The Visible and Infrared Spectrograph channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer is acquiring a global map of spectral reflectance from 300 to 1450 nm wavelength at a range of incidence and emission angles. Targeted areas have been selected for spectral coverage into the ultraviolet with the Ultraviolet and Visible Spectrometer (UVVS). MESSENGER's Mercury Laser Altimeter is acquiring topographic profiles when the slant range to Mercury's surface is less than 1800 km, encompassing latitudes from 201S to the north pole. Topography over the remainder of the southern hemisphere will be derived from stereo imaging, radio occultations, and limb profiles. MESSENGER's radio science experiment is determining Mercury's gravity field from Doppler signals acquired during frequent downlinks. MESSENGER's Magnetometer is measuring the vector magnetic field both within Mercury's magnetosphere and in Mercury's solar wind environment at an instrument sampling rate of up to 20 samples/s. The UVVS is determining the three-dimensional, time-dependent distribution of Mercury's exospheric neutral and ionic species via their emission lines. During each spacecraft orbit, the Energetic Particle Spectrometer measures energetic electrons and ions, and the Fast Imaging Plasma Spectrometer measures the energies and mass per charge of thermal plasma components, both within Mercury's magnetosphere and in Mercury's solar-wind environment. The primary mission observation sequence will continue for one Earth year, until March 2012. An extended mission, currently under discussion with NASA, would add a second year of orbital observations targeting a set of focused follow-on questions that build on observations to date and take advantage of the more active Sun expected during 2012-2013. MESSENGER's total primary mission cost, projected at $446 M in real-year dollars, is comparable to that of Mariner 10 after adjustment for inflation.

Planetary Science↗

NASA NTRS2019

Implementing CubeSat Avionics Components to Full-Scale Capsule Return Missions

Returning samples from Low Earth Orbit (LEO) is no simple task. Whether the samples are scientific experiments or surveillance footage, engineers must overcome many challenges to achieve mission success. In August of 1960 the first payload recovered from LEO, the Corona capsule, carried “more photographic coverage of the Soviet Union than all previous U-2 missions”. The Corona program proved that re-turning surveillance footage from LEO is possible, the program is still referenced today when designing new sample return missions. Although there are many crucial subsystems that make up a sample return capsule, the avionics subsystem demands the most attention. This paper will discuss how current CubeSat avionics components can be applied to large sample return missions. One advantage of using CubeSat avionics components is that they can fit into a 1.5 U (10x10x15 cm) compartment, leaving more room for the payload. This paper is broken down as follows. First, the reader is introduced to the history of sample return projects. The major design strengths of previous projects are analyzed and applied to the current capsule design. Next, the typical trajectory of a capsule is presented along with mission requirements and operations. During the re-entry phase, the avionics subsystem is responsible for commanding the deployment of the parachute, back shell, and the heat shield. Next, the power subsystem is discussed in detail including a trade study on batteries and voltage regulators. Next, the interface between the Ground Support Equipment (GSE) and the avionics components is discussed. It is important that the capsule is able to provide avionics system state of health to ensure proper functionality before the capsule is launched. Next, an in-depth analysis of current TechEdSat avionics components, with proven flight history, are presented. The various avionics components including the radios, GPS, IMU, temperature sensors, altitude sensors, and ejectors are discussed. The application of cur-rent avionics components to a sample return projects are analyzed. After, the wiring diagram is presented along with a discussion of the design. Next, a summary of how the avionics components are tested and validated is pro-vided. Finally, this article will present current sample return missions TechEdSat avionics components are being applied to. CubeSat Avionics can be applied to almost all sample return missions due to their compact configuration and proven space flight heritage. The TechEdSat team is currently making great progress in returning samples from the International Space Station (ISS) and is excited to present how their avionics components can be applied to a full-scale sample return mission.

Hughes, Z. M.↗

NASA NTRS1990

Science strategy and rationale for robotic missions to Mars

The scientific rationale for robotic missions to Mars follows a strategy in which a global data set and general understanding of the planet proceeds to progressively greater detail about specific scientific questions and candidate landing sites. In particular, a global understanding of Mars will be obtained from the Mars Observer mission and the Network Mission. The Site Reconnaissance Orbiter and the Sample Return mission will allow extensive testing and reevaluation of the knowledge about Mars and potential landing sites. Finally, a number of Rovers will provide detailed information on trafficability, resource availability, habitability, and science potential of candidate landing sites. The robotic mission set will also identify important scientific questions that can be addressed at potential landing sites.

Golombek, Matthew↗

NASA NTRS1988

Tropical Rainfall Measurement Mission

It has long been noted that anomalies in the sea surface temperature (SST) in the tropics are strongly correlated with climate in the temperate latitudes on a seasonal time scale. The ability to measure the global SST and the atmospheric pressure/temperature patterns has made great progress. However, rainfall measurement, the putative connection between the two, is poorly accomplished. The Tropical Rainfall Measurement Mission (TRMM) was conceived to fill this gap. The TRMM spacecraft would fly in a low inclination, (about 35 deg), orbit which would concentrate the sampling in the very important tropical latitudes. The precession of such an orbit would enable observations at all times of the day over the span of a month which would permit corrections for the diurnal cycle of precipitation which is quite marked in parts of the tropics. The payload of the TRMM spacecraft is carefully designed to provide accurate measurements of rain. It consists of microwave radiometers, a microwave radar and visible/infrared radiometer. The two types of microwave instruments provide direct measurements of the hydrometeors, each having strengths which compensate for weaknesses of the other. The VIS/IR instrument provides a connection to the long time series of VIS/IR measurements from polar and Geosynchronous spacecraft which are currently the best available source of global rainfall estimates. The TRMM is currently in a phase A (feasibility) study.

Wilheit, T. T.↗

NASA NTRS2022

Advanced Technology Infusion into a Spacesuit System

Advancement in technology drives our future. Moreover, the successful implementation of a technology drives its possibilities. The National Aeronautics and Space Administration (NASA) has invested in numerous technologies over the decades. A quote from NASA’s Space Technology Mission Directorates indicates the importance of technology: “Historically, technology has driven humanity’s progress and will continue to define our future. Our nation chooses to invest in new technology not only to maintain our edge in the global economy but also because technology helps us: Redefine the possible; Create a technologically advanced future; and Drive economic growth.” It is difficult for a technology to satisfy these goals unless it can be successfully infused into a system. For a technology to continue to evolve, become a reality, and infuse into NASA’s missions, there must exist a compilation of success-oriented factors for the technology to reach fruition. Understanding these factors could help decrease the complexity of technology infusion and bridge the gap between technology developers and system integrators. Ultimately, the knowledge gained could facilitate the design, development, and infusion of a technology to be more effective and efficient. Successful technology infusion is complex. Even complexity at the interfaces can be daunting when advanced technology’s infuse into complex systems such as a spacesuit. Additionally, unforeseen emergent behavior and challenges can surface upon integration. Overall, there is a need to understand and measure the success of infusing an advanced technology into a complex system. Industry and academia desire to quantify performance benefits of technologies integrated into complex systems. This paper will focus advanced technology infusion into a spacesuit system. This research could help NASA and industry’s project managers and system mangers integrate advanced technologies more effectively and efficiently.

Advanced Technology↗

NASA NTRSDate not supplied

Progress in Red vs. Green Propellant Operations: ASCENT Load Operations Lessons Learned

The Green Propellant Infusion Mission (GPIM) [1] is a NASA Space Technology Mission Directorate (STMD) effort to establish via demonstration ASCENT propellant (Advanced Space Craft Energetic Non-Toxic propellant, formerly referred to as AF-M315E) ground operations through on –orbit performance. ASCENT was developed by Air Force Research Laboratory (AFRL) as an increased energy density, reduced toxicity and reduced hazard monopropellant formulation relative to hydrazine. The GPIM team was led by Ball Aerospace and Technologies Corporation (BATC) as Program Management and Principal Investigator with AFRL, Aerojet-Rocketdyne (AR), the United States Space Force Space and Missile Systems Center (USSF/SMC), NASA Glenn Research Center (GRC), NASA Goddard Space Flight Center (GSFC), and NASA Kennedy Space Center (KSC) as Co-Investigators. The AFRL co-investigator role in the GPIM program was to develop the Propellant Ground Support Equipment (PGSE), associated Standard Operating Procedures (SOP) and Check Lists (CL), propellant load, propellant specification standard conventions and analysis methods, decontamination and waste disposal practices. This paper will discuss lessons learned in documentation, crew composition and readiness, equipment readiness, propellant readiness and potential improvements in the PGSE design.

Anthony P Zuttarelli↗

NASA NTRS1982

Space Telescope design status and operations

The Space Telescope design concept is described in the context of the basic mission objectives. The orbiting telescope is designed to have 10 times better resolution, to see 50 times fainter stars and to have a much broader spectral range than the best existing ground observatories. The project is on schedule for launch in early 1985. Hardware assembly and test has started on the optical system, and the primary and secondary mirrors have been polished and coated. The five scientific instruments are beginning hardware assembly. The last major design review for the spacecraft has been completed, and good progress has been accomplished with the implementation of the pointing control system. The mission operations ground system has been defined and is under development. Control center design is complete and the science institute is under construction. The Space Telescope is designed to be serviceable in orbit and will be capable of return to the ground for refurbishment.

Speer, F. A.↗

NASA NTRS2011

Human Exploration of Near-Earth Asteroids via Solar Electric Propulsion

There have been many proposed technologies and architectures to extend a human presence beyond the Moon. Solar electric propulsion (SEP) provides the capability to implement a wide variety of missions with relatively low injected mass to low-Earth orbit. Because of its broad applicability this technology can enable progressively ambitious steps towards Mars by incrementally increasing power. The benefits of SEP are addressed for cis-lunar excursions, near-Earth asteroid exploration, and missions to Phobos and Deimos, and compared to chemical propulsion and nuclear thermal technologies. In particular, SEP expands the range of near-Earth asteroids accessible with a constrained launch capability (IMLEO).

exploration architectures↗

NASA NTRS2015

Planetary Protection Knowledge Gaps for Human Extraterrestrial Missions: Workshop Report

This report on Planetary Protection Knowledge Gaps for Human Extraterrestrial Missions summarizes the presentations, deliberations and findings of a workshop at NASA Ames Research Center, March 24-26, 2015, which was attended by more than 100 participants representing a diverse mix of science, engineering, technology, and policy areas. The main objective of the three-day workshop was to identify specific knowledge gaps that need to be addressed to make incremental progress towards the development of NASA Procedural Requirements (NPRs) for Planetary Protection during human missions to Mars.

Race, Margaret S.↗

NASA NTRS1978

Orbit trim maneuver design and implementation for the 1975 Mars Viking Mission

The Viking Mission included the insertion of two unmanned spacecraft into orbit about Mars and the deployment of a soft-lander from each. A description is presented of the adaptive design and implementation of the spacecraft propulsive maneuvers as these flights progressed, taking into account also the inflight results for the orbital phase of the primary Viking mission. The design process included the selection of target parameters and the minimization of both propellant usage and the effects of execution errors, while complying with mission and operational constraints. All maneuvers performed to trim the spacecraft orbits are considered. Attention is given to navigation requirements, geometry definitions and terminology, maneuver mechanization and constraints, and maneuver capability.

Hintz, G. R.↗

NASA NTRS2019

Dynamic RPS Path to Flight

NASA Glenn Research Center has been pursuing the development of dynamic power conversion for several decades. Candidate NASA missions involve mutli-year travel to far away destinations, or to extreme environments where sunlight does not exist. Human-base mission studies also show that power needs would be beyond the capabilities of solar energy conversion, and instead would require nuclear reactor energy sources, for which the thermal energy must be converted to electricity. Dynamic power conversion technology has developed sufficiently to make a sound engineering argument that it is suitable for these NASA missions. Dynamic conversion power sources have yet to be flown in space, and thus suffer a disadvantage owing to their lack of heritage data on flight missions. One of the largest obstacles for adoption is the uncertainty in reliability of a device with moving parts. However, significant progress has been made toward demonstrating the technology capable in all relevant environments, with the necessary long life. Another hurdle for adoption is the lack of mission, which would drive specific requirements, and provide a solid timeline for technology development endpoint. Until a mission is identified, an alternative approach is necessary to advance a dynamic power conversion system towards flight.

Oriti, Sal↗

NASA NTRS2019

Dynamic RPS Path to Flight - Nuclear and Emerging Technologies for Space

Oriti, Salvatore↗

NASA NTRSDate not supplied

Extending the Duration of Crewed Stays on the Lunar Surface

NASA’s Artemis missions aim to return humans to the Moon for the first time since the Apollo Program. Unlike the Apollo missions, Artemis missions will take advantage of pre-emplaced assets on the lunar surface to support crewed exploration, science, and utilization. Although the initial Artemis surface missions are intended to keep crew on the lunar surface for durations ranging from several days to several weeks, crewed stays of longer periods may provide additional support toward NASA’s Moon to Mars Objectives, including long-term exploration and continuous human lunar presence. If mission durations are extended beyond the expected few weeks, the elements and concepts of operation for the lunar architecture will need to be capable of supporting that extension. This paper uses an integrated systems analysis perspective to examine the architectural considerations of extending the duration of human missions on the lunar surface. By identifying these key architectural considerations, this paper offers insight into how elements and operations might meet the demands of potential future mission concepts. This paper does not recommend changes to NASA’s lunar architecture, and it does not evaluate whether any mission concepts affect the relative satisfaction of the Moon to Mars Objectives. However, if crew do remain on the surface for progressively longer periods of time, the functions and capabilities provided by the assets supporting the crew may need to adjust to support the needs of those missions. The functions and capabilities identified as key to enable such extended duration missions include power generation and storage, logistics delivery, radiation mitigation, provision of medical and exercise capability, abort from the lunar surface, maintenance, and the provision of pressurized volume. For example, the medical capabilities available to the crew may become more extensive, and habitable elements may need to change to support longer crewed periods (and shorter quiescent periods). In some cases, these changes may be accomplished through alterations to use cases, operational changes, or the evolution of lunar surface elements, but in other cases, new elements may be preferable. By identifying key considerations for the functions and capabilities of notional lunar surface elements as the length of each crewed mission is extended from several days to continuous human presence on the Moon, this paper assesses how the elements of NASA’s lunar architecture might support the extension of mission durations. In addition, this analysis can help inform future evaluation of whether such extended duration missions improve NASA’s ability to address its Moon to Mars Objectives.

Garrett M. Carman↗

NASA NTRS2018

WCRP Task Team for the Intercomparison of ReAnalyses (TIRA): Motivation and Progress

Reanalyses have proven to be an important resource for weather and climate related research, as well as societal applications at large. New atmospheric reanalyses in various forms are produced every few years. In addition, land and ocean communities are producing disciplinary uncoupled reanalyses, and regional reanalyses are emerging in addition to global reanalyses. Systems of data information are being developed to facilitate the intercomparison of reanalyses among themselves and with observations and climate change experiments (e.g. CREATE-IP and WRIT). Current research and development in reanalysis is directed at (1) extending the length of reanalyzed period and (2) use of coupled Earth system models for climate reanalysis. While the World Climate Research Programme (WCRP) involvement in the reanalyses communities through its Data Advisory Council (WDAC) has been substantial, for example in organizing international conferences on reanalyses. However, these efforts have previously not included an analysis of the differences among reanalyses and their inherent uncertainties which are important questions for both users and developers of reanalyses. Therefore, the WCRP Task Team for the Intercomparison of ReAnalyses (TIRA) task team has been formed as collaborative effort to address reanalyses role in WCRP. This constitutes a logical progression that fills the needs of the community and contributes to the WCRP mission. The primary charge to TIRA is to develop a reanalysis intercomparison project plan that will attain the following objectives.1)To foster understanding and estimation of uncertainties in reanalysis data by intercomparison and other means)To communicate new developments and best practices among the reanalyses producing centers3)To enhance the understanding of data and assimilation issues and their impact on uncertainties, leading to improved reanalyses for climate assessment4)To communicate the strengths and weaknesses of reanalyses, their fitness for purpose, and best practices in the use of reanalysis datasets by the scientific communityThis contribution outlines the need for a task team on reanalyses, their intercomparison, the objectives of the team and progress thus far. Results for some pilot intercomparisons will also be discussed.

Bosilovich, Michael↗

NASA NTRS2017

WCRP Task Team for the Intercomparison of Reanalyses (TIRA): Motivation and Progress

Reanalyses have proven to be an important resource for weather and climate related research, as well as societal applications at large. Several centers have emerged to produce new atmospheric reanalyses in various forms every few years. In addition, land and ocean communities are producing disciplinary uncoupled reanalyses. Current research and development in reanalysis is directed at (1) extending the length of reanalyzed period and (2) use of coupled Earth system models for climate reanalysis. While WCRPs involvement in the reanalyses communities through its Data Advisory Council (WDAC) has been substantial, for example in organizing international conferences on reanalyses, a central team of reanalyses expertise is not in place in the WCRP structure. The differences among reanalyses and their inherent uncertainties are some of the most important questions for both users and developers of reanalyses. Therefore, a collaborative effort to systematically assess and intercompare reanalyses would be a logical progression that fills the needs of the community and contributes to the WCRP mission. The primary charge to the TIRA is to develop a reanalysis intercomparison project plan that will attain the following objectives.1)To foster understanding and estimation of uncertainties in reanalysis data by intercomparison and other means 2)To communicate new developments and best practices among the reanalyses producing centers 3)To enhance the understanding of data and assimilation issues and their impact on uncertainties, leading to improved reanalyses for climate assessment 4)To communicate the strengths and weaknesses of reanalyses, their fitness for purpose, and best practices in the use of reanalysis datasets by the scientific community. This presentation outlines the need for a task team on reanalyses, their intercomparison, the objectives of the team and progress thus far.

WDA↗