H-alpha filtergrams of the sun on March 7, 1970
H alpha filtergrams of sun during solar eclipse of 7 March 1970, showing bright plage area
Caulk, H.↗
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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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X-ray emissions from the sun
Solar X ray emissions from quiet and active sun compared with radio flux to investigate production mechanisms
Krimigis, S. M.↗
Thermal heliotrope - A passive sun-tracker
Continuous sun tracking device consists of helical bimetallic coil and control mechanism. Coil produces torque and angular displacement with temperature change, and acts as device's driving element. Control mechanism, concentric shading mechanism containing bimetallic sensor coil, controls tracking rate and provides for reset cycle.
Byxbee, R. C.↗
Sun tracker with rotatable plane-parallel plate and two photocells Patent
Sun tracker with rotatable plane-parallel plate and two photocells
Volpe, F. A.↗
Spacecraft sun sensors, NASA space vehicle design criteria /guidance and control/
Design criteria and performance specifications for spacecraft sun sensors
Source record↗
A fine sun sensor for Skylab's Apollo telescope mount
Characteristics, performance tests, and evaluation of electronic modules for fine sun sensor assembly for Apollo telescope mount used in Skylab project
Johnston, J. D.↗
Stability of motion near sun-perturbed earth- moon triangular libration points
Two dimensional motion stability near sun-perturbed earth-moon triangular libration points, using computerized high order treatment
Breakwell, J. V.↗
The calibration of the Wilson-Bappu effect on the sun
Wilson-Bappu effect and asymmetric K line emission in sun
Pasachoff, J. M.↗
The extreme-ultraviolet spectrum of the quiet sun
Quiet sun extreme UV spectrum measurements by OSO-4 Harvard scanning spectrometer, discussing instrument design and experimental results
Dupree, A. K.↗
Determination of the sea surface slope distribution and wind velocity using sun glitter viewed from a synchronous satellite
Sea surface slope distribution and wind velocity determination by sun glitter photography from synchronous satellite
Levanon, N.↗
Study of the determination of the coefficients beta and gamma of the generalized metric of Robertson and of the dynamical oblateness of the sun
Motion of a space probe about a spherical center of attraction is considered, applying the general theory of relativity. Motion of a probe under the influence of the sun's oblateness is also discussed. Estimates of beta, gamma, and J20 using solar probe motion are presented. It is concluded that such measurements are possible if the unknown long-period perturbing acceleration is of the order of 10 to the -11th or -12th power m/sec. sq.
Marchal, C.↗
Lunar ephemeris and selenographic coordinates of the earth and sun for 1971 and 1972
Ephemeris data are presented for each month of 1971 and 1972 to provide a time history of lunar coordinates and related geometric information. A NASA Manned Spacecraft Center modification of the Jet Propulsion Laboratory ephemeris tape was used to calculate and plot coordinates of the earth, moon, and sun. The ephemeris is referenced to the mean vernal equinox at the nearest beginning of a Besselian year. Therefore, the reference equinox changes from one year to the next between 30 June and 1 July. The apparent discontinuity in the data is not noticeable in the graphical presentation, but can be observed in the digital output. The mean equator of epoch is used in all cases. The computer program used to compute and plot the ephemeris data is described.
Hartung, A. D.↗
Lunar ephemeris and selenographic coordinates of the earth and sun for 1973 and 1974
Ephemeris data are presented for each month of 1973 and 1974 to provide a time history of lunar coordinates and related geometric information. A NASA Manned Spacecraft Center modification of the Jet Propulsion Laboratory ephemeris tape was used to calculate and plot coordinates of the earth, moon, and sun. The ephemeris is referenced to the mean vernal equinox at the nearest beginning of a Besselian year. Therefore, the reference equinox changes from one year to the next between 30 June and 1 July. The apparent discontinuity in the data is not noticeable in the graphical presentation, but can be observed in the digital output. The mean equator of epoch is used in all cases. The computer program used to compute and plot the ephemeris data is described.
Hartung, A. D.↗
Lunar ephemeris selenographic coordinates of the earth and sun for 1975 and 1976
Ephemeris data are presented for 1975 and 1976 to provide a time history of lunar coordinates and related geometric information. A Manned Spacecraft Center modification of the Jet Propulsion Laboratory ephemeris tape was used to calculate and plot coordinates of the earth, moon, and sun. The ephemeris is referenced to the mean vernal equinox at the nearest beginning of a Besselian year. Therefore the reference equinox changes from one year to the next between 30 June and 1 July. The apparent discontinuity in the data is not noticeable in the graphical presentation, but can be observed in the digital output. The mean equator of epoch is used in all cases.
Hartung, A. D.↗
Why does the sun sometimes look like a magnetic monopole?
For several months in early 1965 the sun appeared to have large scale magnetic field directed outwards at nearly all latitudes and longitudes. Several independent observations that lead to this puzzling situation are discussed.
Wilcox, J. M.↗
Precise linear sun sensor
An evaluation of the precise linear sun sensor relating to future mission applications was performed. The test procedures, data, and results of the dual-axis, solid-state system are included. Brief descriptions of the sensing head and of the system's operational characteristics are presented. A unique feature of the system is that multiple sensor heads with various fields of view may be used with the same electronics.
Johnston, D. D.↗
Lunar ephemeris and selenographic coordinates of the earth and sun for 1979 and 1980
Ephemeris data are presented in sections for each month for 1979 and 1980 to provide a time history of lunar coordinates and related geometric information. A NASA Manned Spacecraft Center modification of an ephemeris tape was used to calculate and plot coordinates of the earth, moon, and sun. The ephemeris is referenced to the mean vernal equinox at the nearest beginning of a Besselian year. Therefore, the reference equinox changes from one year to the next between 30 June and 1 July. The apparent discontinuity in the data is not noticeable in the graphical presentation, but can be observed in the digital output. The mean equator of epoch is used in all cases. The computer program used to compute and plot the ephemeris data is described in the appendix.
Hartung, A. D.↗
Lunar ephemeris and selenographic coordinates of the earth and sun for 1977 and 1978
Ephemeris data are presented in sections for each month for 1977 and 1978 to provide a time history of lunar coordinates and related geometric information. A NASA Manned Spacecraft Center modification of an ephmeris tape was used to calculate and plot coordinates of the earth, moon, and sun. The ephemeris is referenced to the mean vernal equinox at the nearest beginning of a Besselian year. Therefore, the reference equinox changes from one year to the next between June 30 and July 1. The apparent discontinuity in the data is not noticeable in the graphical presentation, but can be observed in the digital output. The mean equator of epoch is used in all cases. The computer program used to compute and plot the ephemeris data is described in the appendix.
Hartung, A. D.↗