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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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NASA NTRS2017

Calibrating the IXPE Observatory from Ground to Space

The Imaging X-ray Polarimetry Explorer (IXPE) will be the next SMEX mission launched by NASA in 2021 in collaboration with the Italian Space Agency (ASI). IXPE will perform groundbreaking measurements of imaging polarization in X-rays for a number of different classes of sources with three identical telescopes, finally (re)opening a window in the high energy Universe after more than 40 years since the first pioneering results. The unprecedented sensitivity of IXPE to polarization poses peculiar requirements on the payload calibration, e.g. the use of polarized and completely unpolarized radiation, both on ground and in orbit, and can not rely on a systematic comparison with results obtained by previous observatories. In this paper, we will present the IXPE calibration plan, describing both calibrations which will be performed on the detectors at INAF-IAPS in Rome (Italy) and the calibration on the mirror and detector assemblies which will be carried out at Marshall Space Flight Center in Huntsville, Alabama. On orbit calibrations, performed with calibrations sources mounted on a filter wheel and placed in front of each detector when necessary, will be presented as well.

X-ray astronomy Polarimetry Calibratio↗
NASA NTRS2012

Progress and Prospects toward a Space-based Gravitational-Wave Observatory

Over the last few years there has been much activity in the effort to produce a space-based gravitational-wave observatory. These efforts have enriched the understanding of the scientific capabilities of such an observatory leading to broad recognition of its value as an astronomical instrument. At the same time, rapidly developing events in the US and Europe have lead to a more complicated outlook than the baseline Laser Interferometer Space Antenna (LISA) project plan of a few years ago. I will discuss recent progress and developments resulting from the European eLISA study and the SGO study in the US and prospects looking forward.

Baker, John↗
NASA NTRS1990

NASA Marshall Space Flight Center solar observatory report, January to December 1989

A description is provided of the NASA-Marshall's Solar Vector Magnetograph Facility and a summary of its observations and data reduction during January to December 1989 is given. The systems that make up the facility are a magnetograph telescope, and H-alpha telescope, a Questar telescope, and a computer code. The data are represented by longitudinal contours with azimuth plots.

Smith, James E.↗
NASA NTRS2003

Space Studies Board Annual Report, 2003

The Space Studies Board is a unit of the NRC's Division on Engineering and Physical Sciences (DEPS), and it reports to the Division for oversight. DEPS is one of six major program units of the NRC through which the institution conducts its operations on behalf of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. Within DEPS there are a total of 14 boards that cover a broad range of physical science and engineering disciplines and mission areas. Members of the DEPS Committee on Engineering and Physical Sciences provide advice on Board membership and advise on proposed new projects to be undertaken by the Board or its committees. Every 3 years the DEPS Committee also reviews the overall operations of each of its boards. The last review of the SSB was in 2001. The Board meets three times per year to review the activities of its committees and task groups and to be briefed on and discuss major space policy issues. An internal executive committee composed of seven at-large members of the Board meets at least once a year and may convene via conference call at other times to plan for SSB activities and to advise the chair between meetings. All projects proposed to be conducted by standing committees or ad hoctask groups must first be reviewed and approved by the Board or its executive committee, and the Board monitors the progress of the projects throughout the course of the studies.

National Aeronautics and Space Administration(NASA↗
NASA NTRS2017

Terrestrial Gamma Ray Flashes due to Particle Acceleration in Tropical Storm Systems

Terrestrial gamma ray flashes (TGFs) are submillisecond flashes of energetic radiation that are believed to emanate from intracloud lightning inside thunderstorms. This emission can be detected hundreds of kilometers from the source by space-based observatories such as the Fermi Gamma-ray Space Telescope (Fermi). The location of the TGF-producing storms can be determined using very low frequency (VLF) radio measurements made simultaneously with the Fermi detection, allowing additional insight into the mechanisms which produce these phenomena. In this paper, we report 37 TGFs originating from tropical storm systems for the first time. Previous studies to gain insight into how tropical cyclones formed and how destructive they can be include the investigation of lightning flash rates and their dependence on storm evolution. We find TGFs to emanate from a broad range of distances from the storm centers. In hurricanes and severe tropical cyclones, the TGFs are observed to occur predominately from the outer rainbands. A majority of our sample also show TGFs occurring during the strengthening phase of the encompassing storm system. These results verify that TGF production closely follows when and where lightning predominately occurs in cyclones. The intrinsic characteristics of these TGFs were not found to differ from other TGFs reported in larger samples. We also find that some TGF-producing storm cells in tropical storm systems far removed from land have a low number of WWLLN sferics. Although not unique to tropical cyclones, this TGF/sferic ratio may imply a high efficiency for the lightning in these storms to generate TGFs.

Roberts, O. S.↗
NASA NTRS1982

Uranus science with space telescope

The Space Telescope Observatory, scheduled for launch in 1985, is described. The advantages of the space environment and the consequent features of ST performance are given, with Uranus observations as examples. The first generation instruments, including two cameras, two spectrographs and a high speed photometer, are discussed. The Space Telescope Science Institute, which will manage the Observatory, is discussed briefly. The potential scientific interaction with the Voyager 2 encounter of Uranus is also considered.

Caldwell, J.↗
NASA NTRS2016

Challenges with Electrical, Electronics, and Electromechanical Parts for James Webb Space Telescope

James Webb Space Telescope (JWST) is the space-based observatory that will extend the knowledge gained by the Hubble Space Telescope (HST). Hubble focuses on optical and ultraviolet wavelengths while JWST focuses on the infrared portion of the electromagnetic spectrum, to see the earliest stars and galaxies that formed in the Universe and to look deep into nearby dust clouds to study the formation of stars and planets. JWST, which commenced creation in 1996, is scheduled to launch in 2018. It includes a suite of four instruments, the spacecraft bus, optical telescope element, Integrated Science Instrument Module (ISIM, the platform to hold the instruments), and a sunshield. The mass of JWST is approximately 6200 kg, including observatory, on-orbit consumables and launch vehicle adaptor. Many challenges were overcome while providing the electrical and electronic components for the Goddard Space Flight Center hardware builds. Other difficulties encountered included developing components to work at cryogenic temperatures, failures of electronic components during development and flight builds, Integration and Test electronic parts problems, and managing technical issues with international partners. This paper will present the context of JWST from a EEE (electrical, electronic, and electromechanical) perspective with examples of challenges and lessons learned throughout the design, development, and fabrication of JWST in cooperation with our associated partners including the Canadian Space Agency (CSA), the European Space Agency (ESA), Lockheed Martin and their respective associated partners. Technical challenges and lessons learned will be discussed.

EEE Parts↗
NASA NTRS2018

A Small Spacecraft Swarm Deployment and Stationkeeping Strategy for Sun-Earth L1 Halo Orbits

Spacecraft orbits about the Sun-Earth librarian point L1 have been of interest since the 1950s. An L1 halo orbit was first achieved with the International Sun-Earth Explorer-3 (ISEE-3) mission, and similar orbits around Sun-Earth L1 were achieved in the Solar and Heliospheric Observatory (SOHO), Advanced Composition Explorer (ACE), Genesis, and Deep Space Climate Observatory (DSCOVR) missions. With recent advancements in CubeSat technology, we envision that it will soon be feasible to deploy CubeSats at L1. As opposed to these prior missions where one large satellite orbited alone, a swarm of CubeSats at L1 would enable novel science data return, providing a topology for intersatellite measurements of heliophysics phenomena both spatially and temporally, at varying spatial scales.The purpose of this iPoster is to present a flight dynamics strategy for a swarm of numerous CubeSats orbiting Sun-Earth L1. The presented method is a coupled, two-part solution. First, we present a deployment strategy for theCubeSats that is optimized to produce prescribed, time-varying intersatellite baselines for the purposes of collectingmagnetometer data as well as radiometric measurements from cross-links. Second, we employ a loose controlstrategy that was successfully applied to SOHO and ACE for minimized stationkeeping propellant expenditure. Weemphasize that the presented solution is practical within the current state-of-the-art and heritage CubeSat technology,citing capabilities of CubeSat designs that will launch on the upcoming Exploration Mission 1 (EM-1) to lunar orbitsand beyond. Within this iPoster, we present animations of the simulated deployment strategy and resulting spacecrafttrajectories. Mission design parameters such as total v required for long-term station keeping andminimum/maximum/mean spacecraft separation distances are also presented.

Optimal control↗
NASA NTRS2007

CALISTO: A Cryogenic Far-Infrared/Submillimeter Observatory

We present a design for a cryogenically cooled large aperture telescope for far-infrared astronomy in the wavelength range 30 micrometers to 300 micrometers. The Cryogenic Aperture Large Infrared Space Telescope Observatory, or CALISTO, is based on an off-axis Gregorian telescope having a 4 m by 6 m primary reflector. This can be launched using an Atlas V 511, with the only optical deployment required being a simple hinged rotation of the secondary reflector. The off-axis design, which includes a cold stop, offers exceptionally good performance in terms of high efficiency and minimum coupling of radiation incident from angles far off the direction of maximum response. This means that strong astronomical sources, such as the Milky Way and zodiacal dust in the plane of the solar system, add very little to the background. The entire optical system is cooled to 4 K to make its emission less than even this low level of astronomical emission. Assuming that detector technology can be improved to the point where detector noise is less than that of the astronomical background, we anticipate unprecedented low values of system noise equivalent power, in the vicinity of 10(exp -19) WHz(exp -0.5), through CALISTO's operating range. This will enable a variety of new astronomical investigations ranging from studies of objects in the outer solar system to tracing the evolution of galaxies in the universe throughout cosmic time.

Cryogenic Aperture Large Infrared Space Telescope ↗
NASA NTRS1989

An antenna for laser gravitational-wave observations in space

Progress during the past two years on a proposed Laser Gravitational-Wave Observatory in Space (LAGOS) is discussed. Calculated performance for a 10 to the 6th km sized antenna over the frequency range of 10 to the -5th to 1 Hz is given. The sensitivity from 0.001 to 0.1 Hz is expected to be 1 x 10 to the -21st/Hz exp 0.5. Noise sources such as accelerations of the drag-free test masses by random molecular impacts and by fluctuations in the net thermal radiation pressure will limit the sensitivity at lower frequencies. The scientific objectives are the observation of CW gravitational waves from large numbers of binary systems and the detection of pulses which may have been emitted during the period of galaxy formation.

Faller, J. E.↗
NASA NTRS1983

Space station needs, attributes and architectural options. Part 1: Summary

Candidate missions for the space station were subjected to an evaluation/filtering process which included the application of budgetary constraints and performance of benefits analysis. Results show that the initial space station should be manned, placed in a 28.5 deg orbit, and provide capabilities which include a space test facility, satellite service, a transport harbor, and an observatory. A space industrial park may be added once further development effort validates the cost and expanding commercial market for space-processed material. Using the space station as a national space test facility can enhance national security, as well as commercial and scientific interests alike. The potential accrued gross mission model benefit derived from these capabilities is $5.9B without the industrial park, and $9.3B with it. Other benefits include the lowering of acquisition costs for NASA and DoD space assets and a basis for broadening international participation.

Source record↗
NASA NTRS1991

Space Infrared Telescope Facility (SIRTF) telescope overview

The Space Infrared Telescope Facility (SIRTF) will be the first true infrared observatory in space, building upon the technical and scientific experience gained through its two NASA survey-oriented predecessors: the Infrared Astronomical Satellite and the Cosmic Background Explorer. During its minimum five year lifetime, the SIRTF will perform pointed scientific observations at wavelengths from 1.8 to 1200 microns with an increase in sensitivity over previous missions of several orders of magnitude. This paper discusses a candidate design for the SIRTF telescope, encompassing optics, cryostat, and instrument accommodation, which has been undertaken to provide a fulcrum for the development of functional requirements, interface definition, risk assessment and cost. The telescope optics employ a baffled Ritchey-Chretien Cassegrain system with a 1-m class primary mirror, an active secondary mirror, and a stationary facetted tertiary mirror. The optics are embedded in a large superfluid He cryostat designed to maintain the entire telescope-instrument system at temperatures below 3 K.

Schember, Helene↗