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Rhee, J. W.

Publications and source records attributed to Rhee, J. W..

11 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1977

Electrostatic dust transport and Apollo 17 LEAM experiment

The Lunar Ejecta and Meteorite (LEAM) experiment has been in operation since December 1973 when it was deployed in the Taurus-Littrow region of the moon by the Apollo 17 crew. A specialized analysis based on more than twenty-two lunations of the impact data shows that all of the events recorded by the sensors during the terminator passages are essentially lunar surface microparticles carrying a high electrostatic charge. Charged lunar fines held in place by adhesive forces can be ejected into space if the electrostatic stress exceeds the adhesive strength. A simple laboratory test demonstrated that this soil transport can indeed take place at the lunar terminator and in the vicinity of it.

Rhee, J. W.↗
NASA NTRS1976

Electrostatic disruption of lunar dust particles

The possibility that dust particles might explode catastrophically on the lunar surface due to electrostatic charging is examined. For the dark side along the terminator zone, dust balls and compact stony particles of micron and submicron sizes will be blown up if their surface potential is as low as a kilovolt negative. This mechanism does not operate on the sunlit side because the surface potential is only 3.5-20 volts positive.

Rhee, J. W.↗
NASA NTRS1976

Radial distribution of meteoric particles in interplanetary space

The heliocentric distribution of meteoric particles in interplanetary space is derived, with consideration of the Poynting-Robertson effect, interparticle collision processes and cometary dust injection. Radial distribution functions were derived for zodiacal dust, radar meteors and the meteoroids of mass 10 to the -9th to about 10 to the -10th g (normalized to 1 AU). The number density was found to depend on particle size.

Rhee, J. W.↗
NASA NTRS1976

Rotational bursting of interplanetary dust particles

Rotationally induced bursting of interplanetary dust particles by a windmill effect stemming from solar radiation pressure, and eventual elimination of the particles from the solar system, is discussed. A life span on the order of 100,000 years for stony meteoritic material or tektite glass with radii of about 1 cm is arrived at for this process. A life span of a million years is computed for particles containing Fe, Ni, or Al with spin damping effects taken into cognizance. This depletion mechanism operates at a rate two orders of magnitude greater than that of the Poynting-Robertson effect in the case of nonmetallic particles and one order of magnitude greater in the case of metallic particles.

Paddack, S. J.↗
NASA NTRS1975

Rotational bursting of interplanetary dust particles

Solar radiation pressure can cause rotational bursting and eventual elimination from the solar system of asymmetric dust particles by a windmill effect. The life span against this process for metallic particles with radii of 0.00001-0.01 cm ranges from 10 to 10,000 years. The effects of magnetic spin damping have been considered in this estimate. This depletion mechanism works faster than the traditional Poynting-Robertson effect by approximately one order of magnitude for metallic particles and about two-orders of magnitude for nonmetallic particles.

Paddack, S. J.↗
NASA NTRS1974

Origin of fifteen cosmic dust particles intercepted by Pioneer 8 and 9

Consistent data for more than 8 years have been obtained from two identical cosmic dust particle experiments on board the space probes Pioneer 8 and 9. The two spacecraft are in direct heliocentric orbits with perihelia between 0.75 AU and 1.00 AU. On the basis of the data it is concluded that the majority of dust particles having elliptical orbits detected by the two space probes show orbital characteristics of Apollo group asteroids which originated from residual nuclei of short-period comets.

Rhee, J. W.↗
NASA NTRS1974

Preliminary results of a cosmic dust experiment on the moon

A three-axis cosmic dust experiment placed on the lunar surface by the Apollo 17 crew is registering impact parameters of cosmic dust and lunar ejecta. A total of 1117 events have been recorded in eight months of data. Preliminary conclusions on the nature of the data include possible evidence of lunar soil transport associated with the terminators. Particle fluxes have been derived for two of the three sensor systems and for specified conditions of exposure.

Berg, O. E.↗
NASA NTRS1974

Rotational bursting of interplanetary dust particles

Solar radiation pressure is discussed as a cause of rotational bursting, and of eventual elimination of asymmetric dust particles from the solar system, by a windmill effect. The predicted life span with this process for metallic particles with radii of 0.00001 to 0.01 cm ranges from 10 to 10,000 years. The effects of magnetic spin damping were considered. This depletion mechanism works faster than the traditional Poynting-Robertson effect by approximately one order of magnitude for metallic particles and about two orders of magnitude for nonmetallic particles.

Paddack, S. J.↗