Interplanetary dust Research Papers - Academia.edu (original) (raw)
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Recent papers in Interplanetary dust
We present a new and more accurate expression for the radiation pressure and Poynting-Robertson drag forces; it is more complete than previous ones, which considered only perfectly absorbing particles or artificial scattering laws. Using... more
We present a new and more accurate expression for the radiation pressure and Poynting-Robertson drag forces; it is more complete than previous ones, which considered only perfectly absorbing particles or artificial scattering laws. Using a simple heuristic derivation, the equation of motion for a particle of mass m and geometrical cross section A, moving with velocity v through a radiation field of energy flux density S, is found to be (to terms of order )
The dust coma of comet Hale-Bopp was observed in the thermal infrared over a wide range in solar heating (R= 4.90.9 AU) and over the full wavelength range from 3 μm to 160 μm. Unusual early activity produced an extensive coma containing... more
The dust coma of comet Hale-Bopp was observed in the thermal infrared over a wide range in solar heating (R= 4.90.9 AU) and over the full wavelength range from 3 μm to 160 μm. Unusual early activity produced an extensive coma containing small warm ...
We developed a new technique for registration of the far solar corona from ground-based observations at distances comparable to those obtained from space coronagraphs. It makes possible visualization of fine details of studied objects... more
We developed a new technique for registration of the far solar corona from ground-based observations at distances comparable to those obtained from space coronagraphs. It makes possible visualization of fine details of studied objects invisible by naked eye. Here we demonstrate that streamers of the electron corona sometimes punch the dust corona and that the shape of the dust corona
It is very well known fact that dust and dusty plasmas are ubiquitous in the space: from interstellar media, to cometary dust, planetary rings and so on. The phenomena concerning the dust in space, seems to have an immense number of... more
It is very well known fact that dust and dusty plasmas are ubiquitous in the space: from interstellar media, to cometary dust, planetary rings and so on. The phenomena concerning the dust in space, seems to have an immense number of facets. The help for the identification of some of the phenomena, or tracing the new ones, has coming during
Cometary material and pristine interplanetary dust particles (IDPs) best resemble the unaltered components from which our solar system was built because they have remained largely unaltered in a cold undisturbed environment since... more
Cometary material and pristine interplanetary dust particles (IDPs) best resemble the unaltered components from which our solar system was built because they have remained largely unaltered in a cold undisturbed environment since accretion in the outer protoplanetary disk. IDPs might supply more primitive assemblages for laboratory analysis than Stardust samples from comet 81P/Wild 2 but their individual provenances are typically unknown. We speculate that some IDPs collected by NASA in April 2003 may be associated with comet 26P/Grigg-Skjellerup because their particularly pristine character coincides with the collection period that was predicted to show an enhanced flux of particles from this Jupiter-family comet. Some IDPs from this collection contain the most primitive assembly of interstellar matter found to date including an unusually high abundance of presolar grains and very isotopically anomalous and disordered organic matter as well as fine-grained carbonates and an amphibole associated with a GEMS-like object (glass with embedded metals and sulfides) that potentially imply formation in a nebular rather than planetary environment. The two most primitive IDPs may contain assemblages of molecular cloud material at the percent level which is supported by the presence of four rare 17O-depleted presolar silicate grains possibly of supernova(e) origin within one ~ 70 μm 2-sized IDP and the close association of a Group 1 Mg-rich olivine from a low-mass red giant star with a carbonaceous nano-globule of potentially interstellar origin. Our study together with observations of comet 9P/Tempel 1 during the Deep Impact experiment and 81P/Wild 2 dust analyses reveal some compositional variations and many similarities among three Jupiter-family comets. Specifically carbonates and primitive organic matter or amorphous carbon were widespread in the comet-forming regions of the outer protoplanetary disk and not all comets contain as much inner solar system material as has been inferred for comet 81P/Wild 2. The bulk and hotspot hydrogen and nitrogen isotopic anomalies as well as the carbon Raman characteristics of the organic matter in IDPs and the most primitive meteorites are remarkably similar. This implies that the same mixture of molecular cloud material had been transported inward into the meteorite-forming regions of the solar system.
- by J Anthony M McDonnell and +2
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- Geochemistry, Geophysics, Interplanetary dust, Titanium