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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 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS2019

Optical Design for CETUS a Wide-Field 1.5-m Aperture UV Payload Being Studied for a NASA Probe Class Mission Study

As part of a study funded by NASA headquarters, we are developing a probe-class mission concept called the Cosmic Evolution through UV Spectroscopy (CETUS). CETUS includes a 1.5-m aperture diameter telescope with a large field of view (FOV). CETUS includes three scientific instruments: a far ultraviolet (FUV) and near ultraviolet (NUV) imaging camera (CAM); a NUV multiobject spectrograph (MOS); and a dual-channel point/slit spectrograph (PSS) in the Lyman ultraviolet (LUV), FUV, and NUV spectral regions. The large FOV three-mirror anastigmatic (TMA) optical telescope assembly (OTA) simultaneously feeds the three separate scientific instruments. That is, the instruments view separate portions of the TMA image plane, enabling parallel operation by the three instruments. The field viewed by the MOS, whose design is based on an Offner-type spectrographic configuration to provide wide FOV correction, is actively configured to select and isolate numerous field sources using a next-generation micro-shutter array. The two-channel CAM design is also based on an Offner-like configuration. The PSS performs high spectral resolution spectroscopy on unresolved objects over the NUV region with spectral resolving power, R ~ 40,000, in an echelle mode. The PSS also performs long-slit imaging spectroscopy at R ~ 20,000 in the LUV and FUV spectral regions with two aberration-corrected, blazed, holographic gratings used in a Rowland-like configuration. The optical system also includes two fine guidance sensors, and wavefront sensors that sample numerous locations over the full OTA FOV. In-flight wavelength calibration is performed by a wavelength calibration system, and flat-fielding is also performed, both using in-flight calibration sources. We describe the current optical design of CETUS and the major trade studies leading to the design.

space sensors↗
NASA NTRS1997

Outer Planet Mission Studies Neptune Aerocapture

Current and previous studies of orbiter missions to the outer planets have clearly identified high-energy aerocapture as a critical and enabling technology. Aerocapture involves the use of aerodynamic lift to fly a trajectory through a planet's atmosphere to sufficiently decelerate an entry vehicle to capture into planetary orbit. In the past, numerous studies of different configurations of lifting entry vehicles were studied for various planetary orbiter missions which identified aerocapture as a feasible concept yet complex and technically challenging. In order to determine the feasibility of high-speed aerocapture at the outer planets, an accurate trajectory simulation of the flight vehicle is the critical first step in the proposed research. Vehicle response to aerodynamic loading must be predicted accurately in the trajectory simulations. For several Neptune orbiter missions currently under study at the Jet Propulsion Laboratory (JPL), entry velocities relative to the rotating atmosphere ranging from 25 to 30 km/sec, are to be expected. Preliminary trajectory analysis has identified the various flow regimes the entry vehicle is expected to fly in the 8 1% H2 and 19% He atmosphere of Neptune. The size and mass of the vehicle are also determined by the launch vehicle constraints and orbiter spacecraft requirements. For a given baseline arrival conditions of an inertial entry velocity of 28 km/sec and an entry mass of 400 kg, a medium lift (L/D = 1), axisymmetric biconic shaped vehicle was selected in order to satisfy entry corridor width requirements expected for Neptune aerocapture. The analysis summarized in this study indicates that a biconic entry vehicle is a feasible concept for a Neptune aerocapture orbiter mission. The preliminary entry trajectory simulations has demonstrated adequate entry corridor control authority. Furthermore, estimates of the stagnation point heating environment has enabled the preliminary selection of candidate lightweight ceramic TPS materials.

Wercinski, Paul F.↗
NASA NTRS2007

Mission Studies for the Terrestrial Planet Finder - Occulter (TPF-O)

The 2000 decadal survey committee recommended a planet-finding telescope (TPF) capable of detecting and characterizing terrestrial planets orbiting nearby stars and of carrying out "revolutionary" astrophysics research. In response, we have carried out mission studies for TPF-O, a promising version of TPF that makes use of a "regular" telescope plus a free-flying occulter that blocks light from the target star while leaving planet light unattenuated. Our mission studies include design reference missions to carry out both planetary and general-astrophysics research. We will report on the results of these studies and describe their implications for the flight system and ground system.

Heap, S.↗
NASA NTRS1967

Study of life support systems for space missions exceeding one year in duration, phase 1A. Volume 2 - Mission studies

The study covered by this report is a continuation of the work conducted under ' contract NAS 2-3012, Study of Life Support Systems For Space Missions Exceeding One Year In Duration Phase I. The previous work compared biological and chemical food processing systems with a stored food system for hypothetical missions of from 10 to 100 men for one to three years. The follow-on work Phase IA, the subject of this report, reviewed new concepts for waste processing and food manufacture in the closed system such as wastes for radiation shielding, wastes for propulsion, glycerol synthesis using chromatographic reactors, glycerol synthesis using acetylene as an intermediate, animal links, the use of radiophosphors for algae illumination, and new biological system approaches. The most promising of these new concepts were combined with the food producing systems evolved in Phase I and compared for three specific model missions; Earth orbit, lunar and mars. The effects of spacecraft power penalty, leakage rate, radiation shielding requirements and extravehicular expendable requirements were assessed and a cost effectiveness analysis was completed for each mission. The cost analysis compared the launch cost savings of the advanced systems with the R&D costs required to produce a flight ready system. The study results indicate that systems using wastes for radiation shielding, leakage makeup, or EVA expendables are very competitive with the biological and chemical food systems for all missions. The stored food baseline system and wastes for propulsion ranked poorly in the comparison studies.

R. B. Jagow↗
NASA NTRS1991

Status of robotic mission studies for the Space Exploration Initiative - 1991

Results of studies of robotic missions to the moon and Mars planned under the U.S. Space Exploration Initiative are summarized. First, an overall strategy for small robotic missions to accomplish the information gathering required by human missions is reviewed, and the principal robotic mission requirements are discussed. The discussion covers the following studies: the Lunar Observer, the Mars Environmental Survey mission, Mars Sample Return missions using microtechnology, and payloads.

Bourke, Roger D.↗
NASA NTRS1994

Self Assembling Mars Transfer Vehicles: The Preferred Concept of the Space Transfer Concepts and Analysis for Explorations Missions Study

Recently, one of the most comprehensive design studies of conceptual manned Mars vehicles, conducted since the Apollo era Mars mission studies of the 1960's, was completed. One of the tasks of the study involved the analysis of nuclear thermal propulsion spacecraft for Manned Mars exploration missions. This paper describes the specific effort aimed at vehicle configuration design. Over the course of the four year study, three configuration baselines were developed, each reflecting trade study cycle results of sequential phases of the study. Favorable attributes incorporated into the final concept, including a capability for on-orbit self-assembly and ease of launch vehicle packability, represent design solutions to configuration deficiencies plaguing nuclear propulsion Mars spacecraft design since the vehicle archetype originated in the 1950's. This paper contains a narrative summary of significant milestones in the effort, describes the evolution to the preferred configuration, and set forth the benefits derived from its utilization.

Donahue, Benjamin↗
NASA NTRS2017

The Far-Infrared Surveyor Mission Study: Paper I, the Genesis

This paper describes the beginning of the Far-Infrared Surveyor mission study for NASA's Astrophysics Decadal 2020. We describe the scope of the study, and the open process approach of the Science and Technology Definition Team. We are currently developing the science cases and provide some preliminary highlights here. We note key areas for technological innovation and improvements necessary to make a Far-Infrared Surveyor mission a reality.

JWST↗
NASA NTRS1971

Comet rendezvous mission study

Four periodic comets with perihelia between 1980 and 1986 (Encke, d'Arrest, Kipff, and Halley) are used as candidates for the comet rendezvous mission study. All these comet apparitions are especially favorable for rendezvous missions, because of early earth-based comet recovery, good opportunities to view their activity from earth, and reasonable launch vehicle and trajectory requirements for nominal payloads.

Friedlander, A. L.↗
NASA NTRS1988

Mars Rover/Sample Return mission trade studies

Mission trade studies for a preliminary definition of a flight-separable Mars Rover/Sample Return (MRSR) mission are presented. The MRSR initiative consists of two separate mission elements: a Mars Rover and a Mars Sample Return. Various strategies are discussed for completing the interplanetary portion of the MRSR mission. Five mission options which are characterized by different launch configurations are discussed, and the resulting spacecraft mass needed to accomplish the mission is presented relative to the capabilities of launch vehicles assumed to be available during the timeframe under consideration.

Soldner, John K.↗
NASA NTRS2006

Direct Imaging of Stellar Surfaces: Results from the Stellar Imager (SI) Vision Mission Study

The Stellar Imager (SI) is a UV-Optical, Space-Based Interferometer designed to enable 0.1 milli-arcsecond (mas) spectral imaging of stellar surfaces and stellar interiors (via asteroseismology) and of the Universe in general. SI is identified as a "Flagship and Landmark Discovery Mission'' in the 2005 Sun Solar System Connection (SSSC) Roadmap and as a candidate for a "Pathways to Life Observatory'' in the Exploration of the Universe Division (EUD) Roadmap (May, 2005). The ultra-sharp images of the Stellar Imager will revolutionize our view of many dynamic astrophysical processes: The 0.1 mas resolution of this deep-space telescope will transform point sources into extended sources, and snapshots into evolving views. SI's science focuses on the role of magnetism in the Universe, particularly on magnetic activity on the surfaces of stars like the Sun. SI's prime goal is to enable long-term forecasting of solar activity and the space weather that it drives in support of the Living With a Star program in the Exploration Era. SI will also revolutionize our understanding of the formation of planetary systems, of the habitability and climatology of distant planets, and of many magneto-hydrodynamically controlled processes in the Universe. In this paper we will discuss the results of the SI Vision Mission Study, elaborating on the science goals of the SI Mission and a mission architecture that could meet those goals.

Carpenter, Kenneth↗
NASA NTRS1976

US metric study mission to the United Kingdom and the Federal Republic of Germany: Report of the NASA representative (Executive Summary)

The trip report is given of the NASA representative of the U.S. metric study mission to the United Kingdom and the Federal Republic of Germany. The mission was organized and conducted under the aegis of the American National Metric Council to learn at first hand the progress of metrication in the United Kingdom and the progress of metrication in the aerospace industry in both the United Kingdom and the Federal Republic of Germany. Representatives of the mission included a cross section of government, industry, labor, and other segments of the private sector. After general and special meetings in the United Kingdom, U.S. members with aerospace related interests met with aerospace representatives in the Federal Republic of Germany.

Vlannes, P. N.↗
NASA NTRS2006

Interactive Visualization of Parking Orbits Around the Moon: An X3D Application for a NASA Lunar Mission Study

The NASA Integrated Modeling and Simulation (IM&S) project aims to develop a collaborative engineering system to include distributed analysis, integrated tools, and web-enabled graphics. Engineers on the IM&S team were tasked with applying IM&S capabilities to an orbital mechanics analysis for a lunar mission study. An interactive lunar globe was created to show 7 landing sites, contour lines depicting the energy required to reach a given site, and the optimal lunar orbit orientation to meet the mission constraints. Activation of the lunar globe rotation shows the change of the angle between the landing site latitude and the orbit plane. A heads-up-display was used to embed straightforward interface elements.

Murphy, Douglas G.↗