SEARCH · Engineering Papers
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.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Radio astronomy and radio interferometry at microwave frequencies are discussed. Other topics concerning the Deep Space Network include program planning, planetary and interplanetary mission support, tracking and ground based navigation, communications, and station control and system technology.
Cryogenic fluid management (CFM) is an important aspect in the design and operation of spacecraft propellant systems. Consequently, it represents a key technology in the development of future vehicles for orbital transfer, lunar transit and manned interplanetary (i.e., Mars) missions. Because of Marshall Space Flight Center's (MSFC's) leading role in the definition of such vehicles, the center is currently managing and conducting a variety of tests to support development of this technology. The purpose of this paper is to summarize these activities and present their status within the context of CFM technology requirements. The first section reviews MSFC's role, identifies the major emphases and thrusts of its program, and presents the overall schedule. The final part comprises the bulk of the report, and describes at length the objectives, approach and status of each project.
The autonomous optical navigation system technology for the Deep Space 1 (DS1) mission is reported on. The DS1 navigation system will be the first to use autonomous navigation in deep space. The systems tasks are to: perform interplanetary cruise orbit determination using images of distant asteroids; control and maintain the orbit of the spacecraft with an ion propulsion system and conventional thrusters, and perform late knowledge updates of target position during close flybys in order to facilitate high quality data return from asteroid MaAuliffe and comet West-Kohoutek-Ikemura. To accomplish these tasks, the following functions are required: picture planning; image processing; dynamical modeling and integration; planetary ephemeris and star catalog handling; orbit determination; data filtering and estimation; maneuver estimation, and spacecraft ephemeris updating. These systems and functions are described and preliminary performance data are presented.
This viewgraph presentation reviews a number of advanced propulsion technologies for interplanetary spacecraft. The objective of the In Space Propulsion Technology Projects Office is to develop in-space propulsion technologies that can enable and/or benefit near and mid-term NASA science missions by significantly reducing cost, mass, and/or travel times. The technologies profiled are divided into several categories: High Priority (aerocapture, next generation ion propulsion, solar sails); Medium Priority (advanced chemical propulsion, solar electric propulsion, Hall thrusters); Low Priority (solar thermal propulsion); and High Payoff/High Risk (1 g/sq m solar sails, momentum exchange tethers, and plasma sails).
As its name partly indicates, the Delay-Tolerant Networking (DTN) Bundle Protocol is a protocol for delay-tolerant transmission of data via communication networks. This protocol was conceived as a result of studies of how to adapt Internet protocols so that Internet-like services could be provided across interplanetary distances in support of deep-space exploration. The protocol, and software to implement the protocol, is being developed in collaboration among experts at NASA's Jet Propulsion Laboratory and other institutions. No current Internet protocols can accommodate long transmission delay times or intermittent link connectivity. The DTN Bundle Protocol represents a departure from the standard Internet assumption that a continuous path is available from a host computer to a client computer: It provides for routing of data through networks that may be disjointed and may be characterized by long transmission delays. In addition to networks that include deepspace communication links, examples of such networks include terrestrial ones within which branches are temporarily disconnected. The protocol is based partly on the definition of a message-based overlay above the transport layers of the networks on which it is hosted.
The advent of the Space Shuttle era elevated cardiovascular deconditioning from a research topic in gravitational physiology to a concern with operational consequences during critical space mission phases. NASA has identified three primary cardiovascular risks associate with short-duration (less than 18 d) spaceflight: orthostatic intolerance; decreased maximal oxygen uptake; and cardiac arrhythmias. Orthostatic hypotension (OH) was observed postflight in Mercury astronauts, studied in Gemini and Apollo astronauts, and tracked as it developed in-flight during Skylab missions. A putative hypotensive episode in the pilot during an early shuttle landing, and well documented postflight hypotension in a quarter of crewmembers, catalyzed NASA's research effort to understand its mechanisms and develop countermeasures. Shuttle investigations documented the onset of OH, tested mechanistic hypotheses, and demonstrated countermeasures both simple and complex. Similarly, decreased aerobic capacity in-flight threatened both extravehicular activity and post-landing emergency egress. In one study, peak oxygen uptake and peak power were significantly decreased following flights. Other studies tested hardware and protocols for aerobic conditioning that undergird both current practice on long-duration International Space Station (ISS) missions and plans for interplanetary expeditions. Finally, several studies suggest that cardiac arrhythmias are of less concern during short-duration spaceflight than during long-duration spaceflight. Duration of the QT interval was unchanged and the frequency of premature atrial and ventricular contractions was actually shown to decrease during extravehicular activity. These investigations on short-duration Shuttle flights have paved the way for research aboard long-duration ISS missions and beyond. Efforts are already underway to study the effects of exploration class missions to asteroids and Mars.
The Natural Environments Branch at Marshall Space Flight Center is an integral part of many NASA satellite and launch vehicle programs, providing analyses of the space and terrestrial environments that are used for program development efforts, operational support, and anomaly investigations. The space environment capabilities of the Natural Environments Branch at MSFC will be presented. These capabilities include model development, analysis of space and terrestrial related data, spacecraft charging anomaly investigations, surface charging modeling (e.g., Nascap-2k), space environment definition and radiation assessments for electronic parts. All aspects of space and terrestrial design are implemented with the goal of devising missions that are successful from launch to operations in the space environment of LEO, polar, GEO, and interplanetary orbits. We will show examples of recent applications of branch capabilities to NASA missions.
The Natural Environments Branch at Marshall Space Flight Center is an integral part of many NASA satellite and launch vehicle programs, providing analyses of the space and terrestrial environments that are used for program development efforts, operational support, and anomaly investigations. These capabilities include model development, instrument build and testing, analysis of space and terrestrial related data, spacecraft charging anomaly investigations, surface and internal charging modeling, space environment definition, and radiation assessments for electronic parts. All aspects of space and terrestrial design are implemented with the goal of devising missions that are successful from launch to operations in the space environment of LEO, polar, GEO, and interplanetary orbits.
The Natural Environments Branch at Marshall Space Flight Center is integral in developing, maintaining, and investigating NASA missions such as Space Launch Systems (SLS), currently under development, as well as many NASA and other agency satellite missions. We present the space environment capabilities of the Natural Environments Branch at MSFC. These in-house capabilities include model development, analysis of space and terrestrial related data, spacecraft charging anomaly investigations, surface charging modeling including Nascap-2k, space environment definition and radiation parts assessment. All aspects of space and terrestrial design are implemented with the goal of devising missions to be successful at launch and in the space environment of LEO, polar, GEO, and interplanetary orbits. In this poster, we show examples of recent applications of branch capabilities to NASA missions.
As the first interplanetary mission managed by the NASA Goddard Space Flight Center, the Mars Atmosphere and Volatile EvolutioN (MAVEN) had three IT security goals for its ground system: COMPLIANCE, (IT) RISK REDUCTION, and COST REDUCTION. In a multiorganizational environment in which government, industry and academia work together in support of the ground system and mission operations, information security governance, risk management, and compliance (GRC) becomes a challenge as each component of the ground system has and follows its own set of IT security requirements. These requirements are not necessarily the same or even similar to each other's, making the auditing of the ground system security a challenging feat. A combination of standards-based information security management based on the National Institute of Standards and Technology (NIST) Risk Management Framework (RMF), due diligence by the Mission's leadership, and effective collaboration among all elements of the ground system enabled MAVEN to successfully meet NASA's requirements for IT security, and therefore meet Federal Information Security Management Act (FISMA) mandate on the Agency. Throughout the implementation of GRC on MAVEN during the early stages of the mission development, the Project faced many challenges some of which have been identified in this paper. The purpose of this paper is to document these challenges, and provide a brief analysis of the lessons MAVEN learned. The historical information documented herein, derived from an internal pre-launch lessons learned analysis, can be used by current and future missions and organizations implementing and auditing GRC.
Several options are being examined to reduce the costs of spacecraft and deep space missions. One such option is to fly spacecraft in a non-coherent mode, that is, the spacecraft does not carry a transponder and cannot coherently return a Doppler signal. Historically, such one-way data has not been used as the sole data type due to the instability of the onboard oscillator, the use of S-band frequencies, and the corresponding larger error sources which could not be modeled. However, with the advent of high-speed work stations and more sophisticated modeling ability, the possibility of using one-way data is being re-examined. This paper addresses the navigation performance of various one-way data types for use in interplanetary missions.
A conceptual vehicle design enabling fast, piloted outer solar system travel was created predicated on a small aspect ratio spherical torus nuclear fusion reactor. The initial requirements were satisfied by the vehicle concept, which could deliver a 172 mt crew payload from Earth to Jupiter rendezvous in 118 days, with an initial mass in low Earth orbit of 1,690 mt. Engineering conceptual design, analysis, and assessment was performed on all major systems including artificial gravity payload, central truss, nuclear fusion reactor, power conversion, magnetic nozzle, fast wave plasma heating, tankage, fuel pellet injector, startup/re-start fission reactor and battery bank, refrigeration, reaction control, communications, mission design, and space operations. Detailed fusion reactor design included analysis of plasma characteristics, power balance/utilization, first wall, toroidal field coils, heat transfer, and neutron/x-ray radiation. Technical comparisons are made between the vehicle concept and the interplanetary spacecraft depicted in the motion picture 2001: A Space Odyssey.
The impending NASA Artemis mission to the Moon will enable deep space exploration. The planned cadence of crewed Moon missions under Artemis necessitates scalable, safe lunar landings. This paper describes the development of Interplanetary Terminal Procedure Design (iTERP) which leverages current terminal procedure design criteria augmented with lunar physics to support the exploration of the Moon, Mars and beyond. The iTERPS model combines lessons learned from decades of commercial airspace operations with novelties of human space exploration on other worlds. This paper will highlight some of the key functional areas in procedure design safety, training, and operations reimagined for human space flight.
The data harvest from the Voyagers’ (V 1 and V 2) Ultraviolet Spectrometers (UVS) covers encounters with the outer planets, measurements of the heliosphere sky-background, and stellar spectrophotometry. Because their period of operation overlaps with many ultraviolet missions, the calibration of V1 and V2 UVS with other spectrometers is invaluable. Here we revisit the UVS calibration to assess the intriguing sensitivity enhancements of 243% (V1) and 156% (V2) proposed recently. Using the Lyα airglow from Saturn, observed in situ by both Voyagers, and remotely by International Ultraviolet Explorer (IUE), we match the Voyager values to IUE, taking into account the shape of the Saturn Lyα line observed with the Goddard High Resolution Spectrograph on board the Hubble Space Telescope. For all known ranges of the interplanetary hydrogen density, we show that the V1 and V2 UVS sensitivities cannot be enhanced by the amounts thus far proposed. The same diagnostic holds for distinct channels covering the diffuse He i 58.4 nm emission. Our prescription is to keep the original calibration of the Voyager UVS with a maximum uncertainty of 30%, making both instruments some of the most stable EUV/FUV spectrographs in the history of space exploration. In that frame, we reassess the excess Lyα emission detected by Voyager UVS deep in the heliosphere, to show its consistency with a heliospheric but not galactic origin. Our finding confirms results obtained nearly two decades ago—namely, the UVS discovery of the distortion of the heliosphere and the corresponding obliquity of the local interstellar magnetic field (∼40{sup ∘} from upwind) in the solar system neighborhood—without requiring any revision of the Voyager UVS calibration.
The Space Radiation Effects on Inflatable Habitat Materials project provides much needed risk reduction data to assess space radiation damage of existing and emerging materials used in manned low-earth orbit, lunar, interplanetary, and Martian surface missions. More specifically, long duration (up to 50 years) space radiation damage will be quantified for materials used in inflatable structures (1st priority), as well as for habitable composite structures and space suits materials (2nd priority). The data acquired will have relevance for nonmetallic materials (polymers and composites) used in NASA missions where long duration reliability is needed in continuous or intermittent radiation fluxes. This project also will help to determine the service lifetimes for habitable inflatable, composite, and space suit materials.
This Year 2 project provides much needed risk reduction data to assess solar particle event (SPE) and galactic cosmic ray (GCR) space radiation damage in existing and emerging materials used in manned low-earth orbit, lunar, interplanetary, and Martian surface missions. More specifically, long duration (up to 50 years) space radiation damage is quantified for materials used in inflatable structures (1st priority), and habitable composite structures and space suits materials (2nd priority). The data collected has relevance for nonmetallic materials (polymers and composites) used in NASA missions where long duration reliability is needed in continuous or intermittent radiation fluxes.
Space weather predictions related to coronal mass ejections (CMEs) requires understanding how a CME is initiated and how its properties change as it propagates. While some parameters can be measured relatively easily near the Sun, others are much harder to disentangle from projected coronagraph images. Most predictions have been limited to the arrival time of a CME and include little to no information about the CME's internal properties. ANTEATR-PARADE represents the most thorough description of the interplanetary evolution of CMEs in a highly computationally-efficient model. (Kay & Nieves-Chinchilla, 2020) presents the derivation of this model, where we have added an elliptical cross section to the original arrival time model ANTEATR and introduced internal magnetic forces that, combined with the drag, can alter the shape of the central axis and cross section. ANTEATR-PARADE results include the transit time of CMEs, as well as the shape and size, propagation and expansion velocities, density, and magnetic field properties upon impact. We determine the dependence of each output on each of the ANTEATR-PARADE input parameters. For a fast CME, we see that the transit time and propagation velocity depend most strongly on inputs that modify the drag force whereas the inputs affecting the magnetic forces determine the expansion of the CME. We extend to other CMEs and _nd that the sensitivities change with CME scale. Magnetic forces become more important for an average CME whereas the drag force becomes more important for an extreme CME.
One of the major logistical challenges in human space exploration is asset management. This paper presents observations on the practice of asset management in support of human space flight to date and discusses a functional-based supply classification and a framework for an integrated database that could be used to improve asset management and logistics for human missions to the Moon, Mars and beyond.