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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 163 records · Page 9
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NASA NTRS1977

Rocketsonde repeatability of temperature and wind measurements as obtained from rocketsonde network systems

Variability of temperature and wind data obtained close in time is of particular concern since questions exist on whether this variability is due to natural atmospheric variability or arises from instrumental causes. Previously conducted repeatability tests of the U.S. Loki Datasonde instrument indicated rms differences of 1C in temperature and 3 mps in wind. The newer Super Loki Datasonde instrument reaches apogee 20 km higher (about 82 km) than the older system and attains a higher initial fall velocity, thus the heat exchange effects on the measuring components are different. Data were obtained from routine rocketsonde launchings, available in pairs, with time differences of 12 to 120 minutes. Mean values calculated over the altitude range of 30 to 70 km indicate than an rms difference of 1-2 C in temperature and of 3-4 mps in the zonal and meridional components exist. Additional computations in 5-km altitude layers suggest that rms differences do not exceed 3 C and 7 mps at the highest altitudes.

Schmidlin, F. J.↗
NASA NTRS1977

Electrification of the proof mass of a drag-free or accelerometric satellite

The exploitation of the data provided by the Cactus accelerometer, which makes up the payload of the D5B Castor Satellite of CNES confirmed the existence of an electric current charging the proof mass under the influence of the magnetospheric protons, and revealed a periodic variation of this current, due to the passage of the apogee through the South Atlantic magnetic anomaly. Results of in-orbit measurements of this charging current are presented, as well as calculations made for determining this current and its variations from data on proton flux at the satellite altitudes. The comparison of measured and calculated values shows that the calculation method is valid and precise enough to be used for drag-free or accelerometric satellites.

Juillert, R.↗
NASA NTRS1977

Ionospheric and magnetospheric plasmapauses'

During August 1972, Explorer 45 orbiting near the equatorial plane with an apogee of about 5.2 R sub e traversed magnetic field lines in close proximity to those simultaneously traversed by the topside ionospheric satellite ISIS 2 near dusk in the L range 2-5.4. The locations of the Explorer 45 plasmapause crossings during this month were compared to the latitudinal decreases of the H(+) density observed on ISIS 2 near the same magnetic field lines. The equatorially determined plasmapause field lines typically passed through or poleward of the minimum of the ionospheric light ion trough, with coincident satellite passes occurring for which the L separation between the plasmapause and trough field lines was between 1 and 2. Vertical flows of the H(+) ions in the light ion trough as detected by the magnetic ion mass spectrometer on ISIS were directed upward with velocities between 1 and 2 kilometers/sec near dusk on these passes. These velocities decreased to lower values on the low latitude side of the H(+) trough but did not show any noticeable change across the field lines corresponding to the magnetospheric plasmapause.

Grebowsky, J. M.↗
NASA NTRS1977

Satellite situation report, volume 17, no. 5

Space objects in orbit are listed as well as those which decayed during this reporting period. Data provided include international designation and catalog number, nation of source, launch data, inclination, apogee and perigee. Transmitting frequencies for satellites being monitored by NASA space flight tracking and data network are given.

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NASA NTRS1977

Satellite situation report, volume 17, no. 6

Space objects in orbit are listed as well as those which decayed during this reporting period. Data provided include international designation and catalog number, nation of source, launch data, inclination, and apogee and perigee. Transmitting frequencies for satellites being monitored by NASA space flight tracking and data network are given.

Source record↗
NASA NTRS1977

International Sun-Earth Explorer - A three-spacecraft program

The International Sun-Earth Explorer (ISEE) is a three-spacecraft system developed by NASA and ESA to study the magnetospheric structure, paying attention to the quantitative mechanism of magnetospheric response to external perturbations, and the structure of its parts. In particular, the nature, structure, motion, and stability of magnetospheric boundaries will be studied, including bow shock, magnetopause, plasmapause, and neutral sheet. Spacecraft ISEE-A and ISEE-B will be launched into the same orbit (of apogee 23 earth radii) but separated by a small, controllable distance, and will make observations from within the magnetosphere. The ISEE-C spacecraft will be launched into a heliocentric orbit (234 earth radii upstream) and will make observations in the solar wind upstream of the earth.

Ogilvie, K. W.↗
NASA NTRS1977

Lageos orbital acquisition and initial assessment

Orbital elements for the satellite Lageos, launched on 4 May, 1976, were generated through use of Baker-Nunn camera data. Camera observations of the apogee kick motor provided the node and perigee, the inclination and the eccentricity, while the mean anomaly and the mean motion were determined from observations of the satellite. During the month following the launch, the Smithsonian Astrophysical Observatory and NASA laser tracking networks acquired about 110 satellite passes. The laser tracking system has been applied to a variety of orbital configurations, including elevation angles below 20 deg. Single-pass range residuals versus time were plotted for 741 laser observations of the satellite; the standard deviation of the total system noise was found to be 7 cm.

Pearlman, M. R.↗
NASA NTRS1976

EDIN0621B Sizing and Performance Results

A launch vehicle was investigated for the Solar Power Satellite System (SPS). The technology level assumed for sizing was that predicted for 1995. The candidate concept designated EDIN0621B is a two stage, winged, series burn vehicle capable of delivering a one million pound payload to low earth orbit. A propulsion system was sized to provide payload circularization at apogee. Any docking, rendezvous or additional Delta V requirements were assumed to be integral to the payload. The EDIN0621B concept used LOX/C3H8 booster engines and uprated Shuttle System main engines in the upper stage. Gross liftoff weight of the baseline vehicle was 18,367,853 pounds. The booster stage required thirteen engines; the upper stage required seven. The vehicle was designed to a liftoff thrust to weight ratio of 1.3.

Hirsch, G. N.↗
NASA NTRS1978

Tabulated data from the SAS-2 high energy gamma ray telescope

The second small astronomy satellite (SAS-2) carried a high energy gamma ray telescope into an equitorial orbit with a 2 D inclination, an apogee of 610 km, and a perigee of 440 km. The energy threshold of the instrument was about 30 MeV, the energy of the gamma rays could be measured up to about 200 MeV, and the integral intensity above 200 MeV could also be measured. Summary tables of the gamma ray data are presented in two energy bands, 35-100 MeV and 100 MeV. The sky was divided into 144 solid angle elements, and, in each solid angle element for which data exist, the number of gamma rays observed is given and also the exposure factor. Information is provided to permit conversion of these data into approximate intensities.

Fichtel, C. E.↗
NASA NTRS1979

Terrier Black Brant VC design characteristics and program status

In the present paper, the design analysis of the Terrier-Black Brant VC, representing the latest addition to the Black Brant rocket family, is discussed, including the aerodynamic, structural, thermal, and operational aspects. An appreciable increase in apogee, as compared to the BBVC and Nike/BBVC, is achieved without any modifications to the well-proven BBV motor or degradation of the thermal or dynamic flight environment.

Payne, B. R.↗
NASA NTRS1979

Depletion of satellite atoms in a collisionless exosphere by radiation pressure

Perturbations of hydrogen atoms in Keplerian orbits are examined by analyzing the rates of change of the classical orbital elements. There are three main effects: high inclination orbits with eccentricities e at least 0.4 are forced toward the ecliptic plane within a few weeks, the perigees of direct orbits drift rapidly toward stable positions roughly westward of the planet, and satellite orbits in or near such a stable point rapidly lower their perigees and the satellite's life is ended by a collision in the atmosphere. Thus there are effects tending to diminish the number of highly eccentric orbits with distant apogees in six principal directions. The various lifetimes are compared for a sample of initial elements.

Chamberlain, J. W.↗
NASA NTRS1979

Determination of the auroral O/1S/ production sources from coordinated rocket and satellite measurements

This paper examines the auroral excitation mechanisms using data collected in a satellite/rocket/aurora coordination. Past theories considered that variation with altitude of the emission from the O(1S) state is the same as that from the N2(+) first negative band system. Actually, the source function for O(1S) does not covary with N2(+) but has a smaller scale height. The covariation is due to quenching of the source function by O(3P). The steadiness of the aurora in a flight of the Michigan Airglow Payload allows the profile to be differentiated for direct comparison with theory. It is concluded that when most of the relevant variables for production of the O(1S) state are simultaneously measured in aurora, the major source functions are dissociative recombination of O2(+) above 210 km to apogee at 250 km, and below 180 km the energy transfer from N2(A3sigma) in the oxygen atom quenching reaction.

Sharp, W. E.↗
NASA NTRS1980

Active experiments using rocket-borne shaped charge barium releases

A reliable payload system and scaled down shaped charges were developed for carrying out experiments in solar-terrestrial magnetospheric physics. Four Nike-Tomahawk flights with apogees near 450 km were conducted to investigate magnetospheric electric fields, and two Taurus-Tomahawk rockets were flown in experiments on the auroral acceleration process in discrete auroras. In addition, a radial shaped charge was designed for plasma perturbation experiments.

Wescott, E. M.↗
NASA NTRS1979

Chorus, energetic electrons and magnetospheric substorms

The paper investigates possible chorus generation mechanisms by means of simultaneous OGO-5 measurements of chorus, energetic (79 + or - 23 keV) electron fluxes and pitch angle distributions, and ambient magnetic fields. Further, the solar wind data during high-latitude dayside chorus events are examined. It is reported that the highly eccentric orbit had an apogee of 24 earth radii and an inclination of 30 deg to the geographic equator.

Tsurutani, B. T.↗
NASA NTRS1980

Magsat - A new satellite to survey the earth's magnetic field

The Magsat satellite was launched on Oct. 30, 1979 into a sun-synchronous dawn-dusk orbit, of 97 deg inclination, 350 km perigee, and 550 km apogee. It contains a precision vector magnetometer and a cesium-vapor scalar magnetometer at the end of a 6-m long graphite epoxy scissors boom. The magnetometers are accurate to 2 nanotesla. A pair of star cameras are used to define the body orientation to 10 arc sec rms. An 'attitude transfer system' measures the orientation of the magnetometer sensors relative to the star cameras to approximately 5 arc sec rms. The satellite position is determined to 70 meters rms by Doppler tracking. The overall objective is to determine each component of the earth's vector magnetic field to an accuracy of 6 nanotesla rms. The Magsat satellite gathers a complete picture of the earth's magnetic field every 12 hours. The vector components are sampled 16 times per second with a resolution of 0.5 nanotesla. The data will be used by the U.S. Geological Survey to prepare 1980 world magnetic field charts and to detect large-scale magnetic anomalies in the earth's crust for use in planning resource exploration strategy.

Mobley, F. F.↗
NASA NTRS1981

NASA to launch second business communications satellite

The two stage Delta 3910 launch vehicle was chosen to place the second small business satellite (SBS-B) into a transfer orbit with an apogee of 36,619 kilometers and a perigee of 167 km, at an inclination of 27.7 degrees to Earth's equator. The firing and separation sequence and the inertial guidance system are described as well as the payload assist module. Facilities and services for tracking and control by NASA, COMSAT, Intelsat, and SBS are outlined and prelaunch operations are summarized.

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NASA NTRS1981

Chemiluminescence of nitric oxide

Measurements of the intensities of the delta and gamma bands of nitric oxide in the nighttime terrestrial thermosphere are presented and used to infer the rate coefficient for the transition from the C 2 Pi to the A 2 Sigma + states. The nightglow spectrum was observed between 1900 and 2300 A at a resolution of 15 A by a rocket-borne scanning 1/4-m spectrometer pointing north at an apogee of 150 km. Progressions of the delta, gamma and epsilon bands are identified on the spectra by the construction of synthetic spectra, and the contributions of resonance fluorescence to the total band intensities are calculated. Finally, the ratio of the sum of the gamma bands for v-prime = 0 to the sum of the delta bands for v-prime = 0 is used to derive a branching ratio of 0.21 + or - 0.04 to the A 2 Sigma + state, which yields a probability for the C-A transition of 5.6 + or - 1.5 x to the 6th/sec.

Sharp, W. E.↗
NASA NTRS1980

National Oceanic and Atmospheric Administration /NOAA/ contamination monitoring instrumentation

The JPL has designed and built a plume contamination monitoring package to be installed on a NOAA environmental services satellite. The package is designed to monitor any condensible contamination that occurs during the ignition and burn of a TE-M-364-15 apogee kick motor. The instrumentation and system interface are described, and attention is given to preflight analysis and test.

Maag, C. R.↗