The effect of the dust concentration in the knudsen layer of a comet on initial conditions in models of the dusty gas flow in a comet’s atmosphere

1Mischishina, II
1Taras Shevchenko National University of Kyiv, Kyiv, Ukraine
Kosm. nauka tehnol. 2012, 18 ;(6):57–66
Section: Space Astronomy
Publication Language: Russian
We studied connections between the parameters of the Knudsen layer and collision region of a comet’s atmosphere on the basis of the hydrodynamics simulation of the flow of gas/dust mix in the collision region. The reliability of the results derived for flows with different gas/dust relationships is estimated. The problem is important for the investigation of mechanisms realizing the gas/dust connection within the thin Knudsen layer of a comet’s nuclear. Within the framework of the model proposed we derived a relationship between the optical thickness of a dusty comet’s atmosphere and the dust production rate of a comet’s nuclear and gas parameters on the exterior boundary of the Knudsen layer.
Keywords: comet's atmosphere, dust production rate, gas/dust mix, optical depth
1. Andrienko D. A., Mishchishina I. I. The characteristic property of big dust grains move in a comet atmosphere.  Kinematics Phys. Celestial Bodies, 19 (6), 501—513 (2003) [in Russian].
2. Anisimov S.I. Vaporization of Metal Absorbing  Laser Radiation.  Sov. Phys. JETP, 54 (1), 339—342 (1968) [in Russian].
3. Korsun P.P. Simulation of Cometary Atmospheres Using Monte Carlo Method: Preprint No. ITP-90-74R (Institute for Theoretical Physics AS USSR), 32 p. (Kiev, 1990) [in Russian].
4. Marov M.Ya. Physical properties and models of comets. Astron. vestnik, 28 (4-5), 5—86 (1994) [in Russian].
5. Marov M. Ya., Kolesnichenko A.V., Skorov Yu. V. Numerical modeling of a gas-and-dust flow in the boundary layer of a cometary atmosphere. Astron. vestnik, 29 (3), 243—252 (1995) [in Russian].
6. Mishchishina I.I. The peculiarities of dynamics the coarse dust particles in comet atmosphere: Candidate’s thesis (Manuscript), 135 p.  (Kyiv, 2003) [in Ukrainian].
7. Skorov Yu. V. Nonequilibrium kinetics of rarefied gas in the porous layer of a cometary nucleus. Astron. vestnik, 31 (1), 28—42 (1997) [in Russian].
8. Skorov Yu. V., Korolev A. E. Spatial Structure of the Surface Layer of a Cometary Atmosphere. Astron. vestnik, 32 (4 ), 370—379 (1998) [in Russian].
9. Shul’man L. M. Dynamics of cometary atmospheres. Neutral gas, 243 p. (Nauk.dumka, Kiev, 1972) [in Russian].
10. Shul’man L. M. Cometary nuclei, 232 p. (Nauka, Moscow, 1987) [in Russian].
11. A’Hearn M. F., Millis R. L., Schleicher D. G., et al. The ensemble properties of comets: Results from narrowband photometry of 85 comets. 1976 — 1992.  Icarus, 118, 223—270 (1995).
12. Bisikalo D. V., Marov M. Ya., Shematovitich V. I., Strel’nitskij V. S. The flow of the sublimating gas in the nearnuclear (Knudsen) layer of the cometary coma. Adv. Space Res., 9 (3), 53—58 (1989).
13. Cercignani C. Strong evaporation of a polyatomic gas.  Progr. Astronaut. and Aeronaut., 74, 305—320 (1981).
14. Combi M. R. Neutral cometary atmospheres. III. Acceleration of cometary CN by solar radiation pressure.  Astrophys. J., 241 (10), 830—837 (1980).
15. Combi M. R., Delsemme A. H. Neutral cometary atmospheres. I. An average random walk model for photodissociation in comets.  Astrophys. J., 237 (4), 633—640 (1980).
16. Combi M. R., Delsemme A. H. Neutral cometary atmospheres. II. The production of CN in comets.  Astrophys. J., 237 (4), 641—645 (1980).
17. Combi M. R., Smith W. H. Monte-Carlo particle-trajectory models for neutral cometary gases. I. Models and equations. Astrophys. J., 327 (4), 1026—1043 (1988).
18. Combi M. R., Smith W. H. Monte-Carlo particle-trajectory models for neutral cometary gases. II. The spatial morphology of the lyman-alfa coma.  Astrophys. J., 327 (4), 1044—1059 (1988).
19. Crifo J. F. Are cometary dust mass loss rates deduced from optical emissions relieble?  Interplanetary matter:  10th European regional astronomy meeting of the IAU. 1987, August 24—29, 109 (1987).
20. Crifo J. F. Optical and hydrodynamic implications of comet Halley dust size distributions, ESA SP-278 (1987).
21. Crifo J. F. Improved gas-kinetic treatment of cometary water sublimationand recondensation.  Astron. and Astrophys., 187 (2), 438—452 (1987).
22. Crifo J. F., Fulle M., Komle N. I, Szego K. Nucleus-coma structural relationships: Lessons from physical models.  In COMETS II, M. Festou, H. U Keller, and H. A.Weaver, 780 p. (University of Arizona Press, Arizona, 2005).
23. Davidson B. Comet Knudsen layers.  Space Sci Rev., 138, 207—223 (2008).
24. Gombosi T. I. Dusty cometary atmospheres. Adv. Space Res., 7 (12), 137—145 (1987).
25. Gombosi T. I., Cravens T. E., Nady A. F. Time-dependent dusty gasdynamical flow near cometary nucleai.  Astrophys. J., 293 (1), 328—341 (1985). 
26. Gombosi T. I., Horanyi M. Time-dependent numerical modeling of dust halo formation at comets // Astrophys. J. — 1986. — 311, N 1. — P. 491—500.
27. Harmon J. K., Nolan M. C., Ostro S. J., Campbell D. B. Radar studies of comet nuclei and grain comae // COMETS II / Ed. M. Festou, H. U. Keller, H. A. Weaver. — Arizona: University of Arizona Press, 2005. — 780 p.
28. Ip W. H. On photochemical heating of cometary comae: the cases of H2 O and CO-rich comets // Astrophys. J. — 1983. — 264, N 2. — P. 726—732.
29. Kitamura J. Axisymmetric dusty gas jet in the inner coma of a comet // Icarus. — 1986. — 66, N 2. — P. 241—257.
30. Kitamura J.Axisymmetric dusty gas jet in the inner coma of a comet. II: The case of isolated Jets // Icarus. — 1987. —72, N 3. — P. 555—567.
31. Kitamura Y., Ashihara O., Yamamota T.A model for the hydrogen coma of a comet // Icarus. — 1985. — 61, N 4. — P. 278—295.
32. Knollenberg J. Modelrechnungen zur Staubfertailung in der inneren Koma von Kometen unter spezieller Berucksichtigung der HMC-Daten der Giotto-Mission. 1994, Ph. D. Thesis, Georg-August Universitat zu Gottingen, Gottingen, Germany.
33. Knollenberg J., Kuhrt E., Keller H. Interpretation of HMC images by a combined thermal and gasdynamic model // Earth, Moon, and Planets. — 1996. — 72, N 1-3. — P. 103—112.
34. Marconi M. L., Mendis D. A. The photochemistry and dynamics of a dusty cometary atmosphere // Moon and Planets. — 1982. — 27, N 1. — P. 27—46.
35. Marconi M. L., Mendis D. A. A multi-fluid model of an H2O-dominated dusty cometary atmosphere // Moon and Planets. — 1982. — 27, N 4. — P. 431—452.
36. Marconi M. L., Mendis D. A. Infrared heating of comet Halleys atmosphere // Earth, Moon and Planets. — 1986. — 36, N 3. — P. 249—256.

37. Wallis M. K. Hydrodynamics of the H2O comet // Mon. Notic. Roy. Astron. Soc. — 1974. — 166. — P. 181—189.