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Lately Exposed Amorphous Water Ice on Comet 49P/Arend-Rigaux

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 نشر من قبل V. Venkataraman
 تاريخ النشر 2014
  مجال البحث فيزياء
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Comet 49P/ Arend-Rigaux, thought to be a low activity comet since the 1980s was found to be active in its recent apparitions. Recent analysis of the data obtained from Spitzer observation of the comet in 2006 compared with laboratory spectra has revealed amorphous water ice on the surface. In addition, in 2012 a jet was found to appear during its subsequent perihelion passage as witnessed during an observation carried out on 26th March 2012 using the PRL telescope at Mt. Abu. This confirms recent activity of Comet 49P/Arend-Rigaux due to the volatile subsurface materials exposed after several passages close to the Sun. Our result confirms the subsurface ices on cometary nuclei and insists for more observations for a better understanding.



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