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Title: Heating of Porous Icy Dust Aggregates

Abstract

At the beginning of planetary formation, highly porous dust aggregates are formed through coagulation of dust grains. Outside the snowline, the main component of an aggregate is H{sub 2}O ice. Because H{sub 2}O ice is formed in amorphous form, its thermal conductivity is extremely small. Therefore, the thermal conductivity of an icy dust aggregate is low. There is a possibility of heating inside an aggregate owing to the decay of radionuclides. It is shown that the temperature increases substantially inside an aggregate, leading to crystallization of amorphous ice. During the crystallization, the temperature further increases sufficiently to continue sintering. The mechanical properties of icy dust aggregates change, and the collisional evolution of dust aggregates is affected by the sintering.

Authors:
 [1]
  1. Earth and Environmental Sciences, Nagoya University, Tikusa-ku, Furo-cho, Nagoya 464-8601 (Japan)
Publication Date:
OSTI Identifier:
22663535
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 842; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CRYSTALLIZATION; DECAY; DUSTS; EVOLUTION; ICE; PLANETS; POROUS MATERIALS; PROTOPLANETS; RADIOISOTOPES; SATELLITES; THERMAL CONDUCTIVITY; WATER

Citation Formats

Sirono, Sin-iti. Heating of Porous Icy Dust Aggregates. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA7389.
Sirono, Sin-iti. Heating of Porous Icy Dust Aggregates. United States. doi:10.3847/1538-4357/AA7389.
Sirono, Sin-iti. Sat . "Heating of Porous Icy Dust Aggregates". United States. doi:10.3847/1538-4357/AA7389.
@article{osti_22663535,
title = {Heating of Porous Icy Dust Aggregates},
author = {Sirono, Sin-iti},
abstractNote = {At the beginning of planetary formation, highly porous dust aggregates are formed through coagulation of dust grains. Outside the snowline, the main component of an aggregate is H{sub 2}O ice. Because H{sub 2}O ice is formed in amorphous form, its thermal conductivity is extremely small. Therefore, the thermal conductivity of an icy dust aggregate is low. There is a possibility of heating inside an aggregate owing to the decay of radionuclides. It is shown that the temperature increases substantially inside an aggregate, leading to crystallization of amorphous ice. During the crystallization, the temperature further increases sufficiently to continue sintering. The mechanical properties of icy dust aggregates change, and the collisional evolution of dust aggregates is affected by the sintering.},
doi = {10.3847/1538-4357/AA7389},
journal = {Astrophysical Journal},
number = 1,
volume = 842,
place = {United States},
year = {Sat Jun 10 00:00:00 EDT 2017},
month = {Sat Jun 10 00:00:00 EDT 2017}
}
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