The Mariner 1969 occultation measurements of the upper atmosphere of Mars
Mars upper atmosphere refractivity, free electron number density and plasma temperature altitude profiles from Mariner 1969 radio occultation measurements
Fjeldbo, G.↗
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Lunar occultation observations of Jupiter at 74 cm and 128 cm
Lunar occultation observation of Jupiter by radio telescope, determining one dimensional strip brightness distribution
Gulkis, S.↗
Summary of Mariner 6 and 7 radio occultation results on the atmosphere of Mars
Mariner 6/7 S band radio occultation probe of Mars atmosphere concerning surface pressure, temperature and existence of ionosphere
Fjeldbo, G.↗
S-band occultation experiment for Mariner Mars 1971
S band occultation experiment for Mariner Mars 1971 orbiters, measuring atmospheric density and ionospheric electron density profiles
Cain, D. L.↗
Temperature distributions in the lower atmosphere of Mars from Mariner 6 and 7 radio occultation data
Mars lower atmosphere vertical temperature distributions from Mariner 6 and 7 radio occultation data, using improved trajectory estimates
Hogan, J. S.↗
Simulation and analysis of microwave propagation between occultation satellites
Remote probing of earth atmosphere by refraction measurements of microwaves propagated between occultation satellites
Sargeant, D. H.↗
Latitudinal and longitudinal variation of a planetary atmosphere and the occultation experiment
Planetary atmosphere Mariner spacecraft occultation experiments, showing neglect of latitudinal and longitudinal variations introduce serious errors
Gross, S. H.↗
The neutral atmosphere of Venus as studied with the Mariner V radio occultation experiments
Venus atmosphere determinations by Mariner 5 radio occultation measurements, deriving altitude profiles of refractivity, molecular number density, pressure, temperature and radio frequency absorption
Eshleman, V. R.↗
Results and interpretation of the S-band occultation experiments on Mars and Venus
Mariner S-band occultation experimental data compared with theory for accuracy of physical characteristics of Mars and Venus atmosphere, reviewing data reduction and error analysis
Rasool, S. I.↗
Seeing effects on occultation curves.
Evaluation of seeing effects on the light curve of a stellar occultation by the moon. Some theoretical studies of Fried (1966) and Hulett (1967) on the linear size of the downward-looking seeing disk are cited, showing that the seeing blur amounts to a few centimeters for a star in the zenith and that the linear blur must grow approximately as (sec z) to the 3/2 power. For most observations the seeing blur will not exceed 8 to 10 cm. The limitation on angular resolution imposed by this seeing effect is calculated.
Young, A. T.↗
Mariner 9 S-band Martian occultation experiment - Initial results on the atmosphere and topography of Mars.
A preliminary analysis of 15 radio occultation measurements taken on the day side of Mars between 40 deg S and 33 deg S has revealed that the temperature in the lower 15 to 20 km of the atmosphere of Mars is essentially isothermal and warmer than expected. This result, which is also confirmed by the increased altitude of the ionization peak of the ionosphere, can possibly be caused by the absorption of solar radiation by fine particles of dust suspended in the lower atmosphere. The floor of the classical bright area of Hellas was found to be about 6 km below its western rim and 4 km below the mean radius of Mars at that latitude.
Kliore, A. J.↗
Infrared diameter of IRC + 10216 determined from lunar occultations.
Lunar occultations of IRC + 10216 have been used to determine the size of the regions emitting 2.2-, 3.5-, 4.8-, and 10-micron radiation. The results are interpreted as the first direct measurement of the physical size of a dust shell surrounding a late-type star.
Toombs, R. I.↗
Errors incurred in profile reconstruction and methods for increasing inversion accuracies for occultation type measurements
A method for augmenting the occultation experiment is described for slightly refractive media. This method which permits separation of the components of the gradient of refractivity, appears applicable to most of the planets for a major portion of their atmospheres and ionospheres. The analytic theory is given, and the results of numerical tests with a radially and angularly varying model of an ionosphere are discussed.
Gross, S. H.↗
Error analysis in the Mariner 6 and 7 occultation experiments
The Mariner 6 and 7 occultation experiments provide sets of Doppler residuals from which physical properties of the Martian atmosphere may be derived, such as the ionospheric electron density distribution and the lower atmosphere temperature profile. The Doppler residuals contain both systematic and random errors. The former are removed during the data reduction, and the latter are analyzed to yield error limits on the derived physical properties of the atmosphere.
Stewart, R. W.↗
Error analysis of bent ray radio occultation measurments
There are two types of experimental measurement errors of the Doppler data associated with the radio occultation, random and systematic. Random errors are due to thermal noise in the transmission channel, and the phase lock loop, and quantization error in the digital circuitry. These are called noise type errors. The systematic errors are due to geometric uncertainty and equipment phase instability. Considered is the amount of uncertainty, due to random measurement errors, in the refractivity profiles reconstructed by this type of indirect sensing experiment. A class of refractivity profiles is defined which approximately fit the set of measured data. Bounds are placed on the extent of this class of solution profiles. To accomplish this, the sensivity of the reconstructed refractivity profiles to errors in the measured quantity and the statistics of the errors in the measurement are examined.
Saintgermain, R. L.↗
Photographic observations of the occultation of Beta Scorpii by Jupiter
The occultation of the multiple star Beta Scorpii by Jupiter was observed visually and photographically from the Bosscha Observatory in Lembang (Java), Indonesia, on May 13, 1971. The photographs recorded the dimming of the stars as the light was differentially refracted by the Jovian atmosphere, and gave support to a scale height greater than 8 km. Measurement of the position of the brightest component at Beta Scorpii during ingress shown refraction of approximately 1.4 sec before becoming unobservable.
Larson, S. M.↗
S-band radio occultation measurements of the atmosphere and topography of Mars with Mariner 9: Extended mission coverage of polar and intermediate latitudes
Radio occultation measurements from Mariner 9 orbits around Mars show that the radius of Mars changes by only about 2 km from a latitude of 65 deg to the north pole, that the north polar area is about average in elevation, and that polar temperature profiles are indicative of the possibility that the remnant north polar cap may be at least partially composed of water ice. It is also found that Mars, in addition to being asymmetrical equatorially, is also significantly asymmetrical in the north and south direction with the Southern Hemisphere lying 3 to 4 km higher. Temperature gradients in the clear Martian atmosphere of only about one-half of the adiabatic gradients of 5 deg K/km suggest the importance of dynamical processes.
Kliore, A. J.↗
Remote sensing of the turbulence characteristics of a planetary atmosphere by radio occultation of a space probe.
The purpose of this paper is to analyze the effects of small-scale turbulence on radio waves propagating through a planetary atmosphere. The analysis provides a technique for inferring the turbulence characteristics of a planetary atmosphere from the radio signals received from a spacecraft as it is occulted by the planet. The planetary turbulence is assumed to be localized and smoothly varying, with the structure constant varying exponentially with altitude. Rytov's method is used to derive the variance of log-amplitude and phase fluctuations of a wave propagating through the atmosphere.
Woo, R.↗