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Meteoroid Storms Detected on the Moon
Science, 1976Seismometers on the moon have detected several brief periods of enhanced meteoroid-impact activity, believed to represent encounters of the moon with "clouds" of objects in the kilogram range. The latest and most active encounter, in June 1975, is interpreted as a meteoroid cloud of diameter 0.1 astronomical unit and total mass 10
F K, Duennebier +3 more
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Journal of Geophysical Research, 1963
Estimates of the meteoroid penetration of vehicles in space are improved from the author's 1957 values. The meteoritic data are improved by the measurement of luminous efficiency in the artificial meteor experiment of Trailblazer 1 analyzed by McCrosky and Soberman, and by independent determinations from three asteroidal meteors by Cook, Jaechia, and ...
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Estimates of the meteoroid penetration of vehicles in space are improved from the author's 1957 values. The meteoritic data are improved by the measurement of luminous efficiency in the artificial meteor experiment of Trailblazer 1 analyzed by McCrosky and Soberman, and by independent determinations from three asteroidal meteors by Cook, Jaechia, and ...
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Science, 1968
The meteoroid experiments by five Lunar Orbiters have provided direct measurements in the near-lunar environment of the rate of penetration of 0.025-millimeter beryllium copper by meteoroids. Each experiment used 20 pressurized-cell detectors having a total effective exposed area of 0.186 square meter.
C A, Gurtler, G W, Grew
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The meteoroid experiments by five Lunar Orbiters have provided direct measurements in the near-lunar environment of the rate of penetration of 0.025-millimeter beryllium copper by meteoroids. Each experiment used 20 pressurized-cell detectors having a total effective exposed area of 0.186 square meter.
C A, Gurtler, G W, Grew
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Temperature of an Iron Meteoroid in Space
Science, 1963The solar absorptance and hemispherical emittance of meteoritic iron has been measured from —100° to 300°C for a surface characterized by a 400-grit finish. If it is assumed that 10 percent of the surface is optically black because of holes and cracks, the temperature of an iron meteoroid at the earth's mean distance from the sun would be about 90°C.
C P, Butler, R J, Jenkins
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Il Nuovo Cimento, 1964
The density of 359 photographic meteors, reduced by Hawkins and Southworth, has been computed with a procedure that uses the height of maximum light and does not require the use of the deceleration. The reliability of the method is discussed. It is shown that neither fragmentation nor other known causes can have a large effect on the results.
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The density of 359 photographic meteors, reduced by Hawkins and Southworth, has been computed with a procedure that uses the height of maximum light and does not require the use of the deceleration. The reliability of the method is discussed. It is shown that neither fragmentation nor other known causes can have a large effect on the results.
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1983
We have already mentioned repeatedly the great significance of the fragmentation of meteoroids (see Sections 20, 31, and 34). Now let us consider the main observational data attesting to this phenomenon [194]: (1) a high rate of ablation and, as a result, shorter trajectories and higher fadeout altitudes than are to be expected from the ...
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We have already mentioned repeatedly the great significance of the fragmentation of meteoroids (see Sections 20, 31, and 34). Now let us consider the main observational data attesting to this phenomenon [194]: (1) a high rate of ablation and, as a result, shorter trajectories and higher fadeout altitudes than are to be expected from the ...
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Solar System Research, 2018
The interaction between a large meteoroid and the atmosphere is modeled as its destruction into a cloud of fragments and vapors moving with a common shock wave. Under the action of aerodynamic forces the shape of this cloud is deformed—it is expanded in the direction transverse to the motion and compressed in the longitudinal direction.
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The interaction between a large meteoroid and the atmosphere is modeled as its destruction into a cloud of fragments and vapors moving with a common shock wave. Under the action of aerodynamic forces the shape of this cloud is deformed—it is expanded in the direction transverse to the motion and compressed in the longitudinal direction.
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Modeling of meteoroid streams: The velocity of ejection of meteoroids from comets (a review)
Solar System Research, 2013An analytical review of the models of ejection of meteoroids from cometary nuclei is presented. Different formulas for the ejection velocity of meteoroids and the corresponding parameters are discussed and compared with the use of comet Halley and the Geminids meteoroid stream as examples.
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1983
Ablation is defined as a removal of meteoroid mass via phase transformations of the solid surface layer to the liquid or gaseous state. Ablation involves: (a) fusion of the outer layer, followed by spraying of the liquid layer by the oncoming air flow; (b) vaporization of the solid phase or liquid layer, and removal of mass in the ...
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Ablation is defined as a removal of meteoroid mass via phase transformations of the solid surface layer to the liquid or gaseous state. Ablation involves: (a) fusion of the outer layer, followed by spraying of the liquid layer by the oncoming air flow; (b) vaporization of the solid phase or liquid layer, and removal of mass in the ...
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Temperatures of Meteoroids in Space
Meteoritics, 1966Abstract On the basis of reported optical measurements of iron and stony meteorites, upper and lower limits for solar absorptance and hemispherical emittance of the surfaces of meteoroids have been established. Temperatures of three classes of meteoroids, none larger than approximately 10 meters in radius, have been calculated for various orbits and a ...
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