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61.
Marc Fries Lucille Le Corre Mike Hankey Jeff Fries Robert Matson Jake Schaefer Vishnu Reddy 《Meteoritics & planetary science》2014,49(11):1989-1996
The Sutter's Mill C‐type meteorite fall occurred on 22 April 2012 in and around the town of Coloma, California. The exact location of the meteorite fall was determined within hours of the event using a combination of eyewitness reports, weather radar imagery, and seismometry data. Recovery of the first meteorites occurred within 2 days and continued for months afterward. The recovery effort included local citizens, scientists, and meteorite hunters, and featured coordination efforts by local scientific institutions. Scientific analysis of the collected meteorites revealed characteristics that were available for study only because the rapid collection of samples had minimized terrestrial contamination/alteration. This combination of factors—rapid and accurate location of the event, participation in the meteorite search by the public, and coordinated scientific investigation of recovered samples—is a model that was widely beneficial and should be emulated in future meteorite falls. The tools necessary to recreate the Sutter's Mill recovery are available, but are currently underutilized in much of the world. Weather radar networks, scientific institutions with interest in meteoritics, and the interested public are available globally. Therefore, it is possible to repeat the Sutter's Mill recovery model for future meteorite falls around the world, each for relatively little cost with a dedicated researcher. Doing so will significantly increase the number of fresh meteorite falls available for study, provide meteorite material that can serve as the nuclei of new meteorite collections, and will improve the public visibility of meteoritics research. 相似文献
62.
Axially symmetric cosmological models with cosmic string source are obtained in a scalar-tensor theory of gravitation proposed
by Saez and Ballester (Phys. Lett. A113, 467, 1985). The models obtained give us axially symmetric geometric (Nambu) string, p-string and Reddy string (Astrophys. Space Sci. 286, 2003b) in Saez-Ballester theory. Some physical properties of the models are also discussed. 相似文献
63.
64.
65.
Bianchi type-IX space-time is considered in the presence of cosmic string source in the frame work of a scalar- tensor theory
of gravitation proposed by Saez and Ballester (Phys. Lett. A 113:467, 1985). Exact cosmological models representing geometric (Nambu) string, p string and baratropic string are discussed in this theory.
Some physical and kinematical properties of the models are also studied. 相似文献
66.
D. R. K. Reddy 《Astrophysics and Space Science》1987,133(1):189-191
The field equations of the self-creation theory of gravitation proposed by Barber are solved for a vacuum with the aid of a space-time metric of Friedmann. Some physical properties of the solution are discussed. 相似文献
67.
A spatially-homogeneous and anisotropic-cosmological model in a scalar-tensor theory proposed by Sen and Dunn (1971) is obtained when the source of the gravitational field is a perfect fluid with pressure equal to energy density and the metric is of Bianchi type-I. Various physical properties of the model have also been discussed. 相似文献
68.
D. R. K. Reddy 《Astrophysics and Space Science》1987,138(1):121-125
The Einstein field equations for an irrotational perfect fluid with pressurep, equal to energy density are studied when the space-time is conformally flat. The coordinate transformation to co-moving coordinates is discussed. The energy and Hawking-Penrose inequalities are studied. Static and non-static solutions of the field equations are obtained. It is interesting to note that in the static case the only spherically-symmetric conformally flat solution for self-gravitating fluid is simply the empty flat space-time of general relativity. 相似文献
69.
D.R.K. Reddy 《Astrophysics and Space Science》2003,286(3-4):359-363
An exact Boanchi type -I string cosmological model is obtained in a scalar-tensor theory of gravitation proposed by Saez and
Ballester (1985). Some physical properties of the model are also discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
70.
D. R. K. Reddy 《Astrophysics and Space Science》1988,140(1):161-164
A non-static plane-symmetric cosmological model in the presence of zero-mass scalar fields is obtained when the source of the gravitational field is a perfect fluid with pressure equal to energy density. Some properties of the model are discussed. 相似文献