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On the deceleration of cometary fragments in aerogel

Published online by Cambridge University Press:  22 December 2008

S.G. Coulson
Affiliation:
Centre for Astrobiology, School of Mathematics, Cardiff University, 2 North Road, Cardiff CF10 3DY, UK e-mail: [email protected]

Abstract

Determining the thermal history of the cometary grains captured by the Stardust mission presents a difficult problem. We consider two simplified models for the deceleration of hypervelocity particles captured in aerogel; both models assume a velocity squared drag force. The first model assumes that the mass of the particle remains constant during capture and the second that mass is lost due to ablation of the particle through interactions with the aerogel. It is found that the constant mass model adequately reproduces the track lengths, found from experiments by Hörz et al. in 2008, that impacted aluminium oxide spheres into aerogel at hypervelocities ~6 km s−1.

Deceleration in aerogel heats volatile particles such as organic ices to high temperatures greater than 1,000 K, for durations of ~1 μs: more than sufficient to completely ablate the particle. Refractory particles also experience significant heating greater than 2500 K, greater than the particle's melting point, over similar timescales. This suggests that the fragments recovered to Earth by the Stardust mission were considerably altered by hypersonic capture by aerogel, and so limits the amount of information that can be obtained regarding the formation of mineral and organic particles within Kuiper Belt comets.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2008

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References

Anderson, W.W. (1988). Physics of interplanetary dust collection with aerogel. NASA STI/Recon Technical Report, NASACR-1988-207766.Google Scholar
Bronhsten, V.A. (1983). Physics of Meteoric Phenomena, Dordrecht, Holland, D. Reidal Publishing Co.CrossRefGoogle Scholar
Brownlee, D.E., Tsou, P., Anderson, J.D., Hanner, M.S., Newburn, R.L., Sekanina, Z., Clark, B.C., Hörz, F., Zolensky, M.E., Kissel, J., McDonnell, J.A.M., Sandford, S.A. & Tuzzolino, A.J. (2003). JGR 108(E10), 811.CrossRefGoogle Scholar
Brownlee, Donald E., Horz, Friedrich, Newburn, Ray L., Zolensky, Michael, Duxbury, Thomas C., Sandford, Scott, Sekanina, Zdenek, Tsou, Peter, Hanner, Martha S., Clark, Benton C., Green, Simon F. & Kissel, Jochen (2004). Science 304, 17641769.CrossRefGoogle Scholar
Brownlee, Don, Tsou, Peter, Aléon, Jérôme, Alexander, Conel M.O.'D., Araki, Tohru, Bajt, Sasa, Baratta, Giuseppe A., Bastien, Ron, Bland, Phil, Bleuet, Pierre, et al. (2006). Science 314, 17111716.CrossRefGoogle Scholar
Burchell, M.J. (2004). Int. J. Astrobiology 3(2), 7380.CrossRefGoogle Scholar
Burchell, M.J., Creighton, J.A., Cole, M.J., Mann, J., Kearsley, A.T. (2001). Met. Planet. Sci. 36, 209221.CrossRefGoogle Scholar
Burchell, M.J., Fairey, S.A.J., Wozniakiewicz, P., Brownlee, D.E., Hörz, F., Kearsley, A.T., See, T.E., Tsou, P., Westphal, A., Green, S.F. et al. (2008). Meteoritics Planet. Sci. 43, 2340.CrossRefGoogle Scholar
Coulson, S.G. (2006). Int. J. Astrobiology 5(4), 307312.CrossRefGoogle Scholar
Coulson, S.G. & Wickramasinghe, N.C. (2003). Mon. Not. R. Astron. Soc. 343, 11231130.CrossRefGoogle Scholar
Coulson, S.G. & Wickramasinghe, N.C. (2007). Int. J. Astrobiology 6(4), 263266.CrossRefGoogle Scholar
Domínguez, Gerardo, Westphal, Andrew J., Jones, Steven M. & Phillips, Mark L.F. (2004). Icarus 172, 613624.CrossRefGoogle Scholar
Hörz, F., Cintala, M.J., See, T.H., Nakamura-Messenger, K. Hörz (Abstract) 39th Lunar and Planetary Science Conference (Lunar and Planetary Science XXXIX), held March 10–14, 2008 in League City, Texas. LPI Contribution No. 1391., p. 1446.Google Scholar
Hoyle, F. & Wickramsinghe, N.C. (1978). Life Cloud. J. M. Dent, London.Google Scholar
Lide, D.R. (ed.) (2008). CRC Handbook of Chemistry and Physics, 89th edn.Florida, CRC Press.Google Scholar
Noguchi, T., Nakamura, T., Okudaira, K., Yano, H., Sugita, S. & Burchell, M.J. (2007) Met. Planet. Sci. 42, 357372.CrossRefGoogle Scholar
Tillotson, T.M. & Hrubesh, L.W. (1992). J. Noncryst. Solids 145, 4450.CrossRefGoogle Scholar
Trigo-Rodriguez, J.M., Dominguez, G., Burchell, M.J., Hörz, F. & Llorca, J. (2008) Met. Planet. Sci. 43, 7586.CrossRefGoogle Scholar
Tsou, P., Brownlee, D.E., Laurance, M.R., Hrubesh, L. & Albee, A.L. (1998). Intact capture of hypervelocity micrometeoroid analogs (abstract). 29th Lunar and Planetary Science Conference. Houston, Texas, Pp. 12051206.Google Scholar
Zolensky, Michael E., Zega, Thomas J., Yano, Hajime, Wirick, Sue, Westphal, Andrew J., Weisberg, Mike K., Weber, Iris, Warren, Jack L., Velbel, Michael A., Tsuchiyama, Akira (2006). Science 314, 17351739.CrossRefGoogle Scholar