Earth, Moon, and Planets

, Volume 117, Issue 1, pp 23–39 | Cite as

Transport and Distribution of Hydroxyl Radicals and Oxygen Atoms from H2O Photodissociation in the Inner Coma of Comet 67P/Churyumov–Gerasimenko

  • Ian-Lin Lai
  • Cheng-Chin Su
  • Wing-Huen Ip
  • Chen-En Wei
  • Jong-Shinn Wu
  • Ming-Chung Lo
  • Ying Liao
  • Nicolas Thomas


With a combination of the Direct Simulation Monte Carlo (DSMC) calculation and test particle computation, the ballistic transport process of the hydroxyl radicals and oxygen atoms produced by photodissociation of water molecules in the coma of comet 67P/Churyumov–Gerasimenko is modelled. We discuss the key elements and essential features of such simulations which results can be compared with the remote-sensing and in situ measurements of cometary gas coma from the Rosetta mission at different orbital phases of this comet.


Comets Comet 67P Atmosphere Photodissociation 



We thank the reviwers for useful comments and suggestions in improving the content of this paper. We are also indebted to Dr. Zhong-Yi Lin, Dr. Dennis Bodewits, Jui-Chi Lee, and the Rosetta OSIRIS science team for helpful discussions. This work was supported by MOST 104-2119-M-008-024 (TANGO II) and MOST 104-2111-M-008-020 (Space) in Taiwan and MSTDF Grant No. 017/2014/A1 and 039/2013/A2 in Macau.


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Copyright information

© Springer Science+Business Media Dordrecht 2016

Authors and Affiliations

  • Ian-Lin Lai
    • 1
  • Cheng-Chin Su
    • 2
  • Wing-Huen Ip
    • 1
    • 3
    • 4
  • Chen-En Wei
    • 3
  • Jong-Shinn Wu
    • 2
  • Ming-Chung Lo
    • 2
  • Ying Liao
    • 5
  • Nicolas Thomas
    • 5
  1. 1.Institute of Space SciencesNational Central UniversityTaoyuan CityTaiwan
  2. 2.Department of Mechanical EngineeringNational Chiao Tung UniversityHsinchu CityTaiwan
  3. 3.Institute of AstronomyNational Central UniversityTaoyuan CityTaiwan
  4. 4.Space Science InstituteMacau University of Science and TechnologyTaipaMacau
  5. 5.Physikalisches InstitutUniversity of BernBernSwitzerland

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