Organics and Other Molecules in the Surfaces of Callisto and Ganymede
Abstract
Five absorption features are reported at wavelengths of 3.4, 3.88, 4.05, 4.25, and 4.57 micrometers in the surface materials of the Galilean satellites Callisto and Ganymede from analysis of reflectance spectra returned by the Galileo mission near-infrared mapping spectrometer. Candidate materials include CO2, organic materials (such as tholins containing C≡N and C-H), SO2, and compounds containing an SH-functional group; CO2, SO2, and perhaps cyanogen [(CN)2] may be present within the surface material itself as collections of a few molecules each. The spectra indicate that the primary surface constituents are water ice and hydrated minerals.
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REFERENCES AND NOTES
1
Special issue on the Galileo Orbiter Observations of Jupiter and Its Satellites, Science 274, 377–403 (18 October 1996); J. D. Anderson, W. L. Sjogren, G. Schubert, ibid. 272, 709 (1996);
Anderson J. D., Lau E. L., Sjogren W. L., Schubert G., Moore W. B., Nature 384, 541 (1996);
; ibid. 387, 264 (1997); Science 276, 1236 (1997).
2
Watson K., Murray B. C., Brown H., Icarus 1, 361 (1963).
3
R. W. Carlson, P. R. Weissman, W. D. Smythe, J. C. Mahoney, the NIMS Science and Engineering Team, Space Sci. Rev. 60, 457 (1992).
4
Early results of the entire NIMS investigation (satellites and Jupiter) were reported previously by
Carlson R., et al., Science 274, 385 (1996).
5
Early results for Callisto and Ganymede were reported by T. B. McCord et al., Bull. Am. Astron. Soc. 28, 1138 (abstr.) (1996); T. B. McCord et al., Trans. Am. Geophys. Union 77, F445 (abstr.) (1996); T. B. McCord et al., ibid.78, S2O2 (abstr.) (1997).
6
Ockman N., Adv. Phys. 7, 199 (1958);
Irvine W. M., Pollack J. B., Icarus 8, 324 (1968);
; P. V. Hobbs, Ice Physics (Clarendon, Oxford, 1974); S. G. Warren, Appl. Opt. 23, 1206 (1984).
7
Fink U., Larson H. P., Icarus 24, 411 (1975).
8
Pilcher C. B., Ridgway S. T., McCord T. B., Science 178, 1087 (1972);
Fink U., Dekkers N. H., Larson H. P., Astrophys. J. 179, L155 (1973);
Pollack J. B., et al., Icarus 36, 271 (1978);
; G. T. Sill and R. N. Clark, in Satellites of Jupiter, D. Morrison, Ed. (Univ. of Arizona Press, Tucson, 1982), pp. 174–212; R. N. Clark, F. P. Fanale, M. J. Gaffey, in Satellites, J. Burns and M. S. Matthews, Eds. (Univ. of Arizona Press, Tucson, 1986), pp. 437–491;
Roush T. L., Pollack J. B., Witteborn F. C., Bregman J. D., Simpson J. P., Icarus 86, 355 (1990);
Calvin W. M., Clark R. N., ibid. 89, 305 (1991);
Calvin W. M., Clark R. N., Brown R. H., Spencer J. R., J. Geophys. Res. 100, 19041 (1995).
9
For spectra of minerals, see R. N. Clark, the USGS Digital Spectral Library 0.2-150 μm, in preparation [see R. N. Clark, G. A. Swayze, A. Gallagher, T. V. V. King, W. M. Calvin, U.S. Geol. Surv. Open File Rep. 93-592 (1993) for 0.2 to 3.0 μm]; J. W. Salisbury, L. S. Walter, N. Vergo, D. M. D'Aria, Infrared (2.1–25 μm) Spectra of Minerals (Johns Hopkins Univ. Press, Baltimore and London, 1991).
10
For spectra of organics, see N. B. Colthup, L. H. Daly, S. E. Wiberley, Introduction to Infrared and Raman Spectroscopy (Academic Press, San Diego, ed. 3, 1990).
11
For spectra of gaseous and frozen volatiles, see
Rothman L. S., et al., J. Quant. Spectrosc. Radiat. Transfer 48, 469 (1992);
; U. Fink and G. T. Sill, in Comets, L. L. Wilkening, Ed. (Univ. of Arizona Press, Tucson, 1982), p. 164;
Pierson R. H., Fletcher A. N., Glantz E. S. C., Anal. Chem. 28, 1218 (1956).
12
R. M. Goody and Y. L. Yung, in Atmospheric Radiation (Oxford Univ. Press, New York, ed. 2, 1989), pp. 67–124.
13
Sandford S. A., Allamandola L. J., Astrophys. J. 355, 357 (1990).
14
Johnson R. E., Jesser W. A., Astron. J. 480, L79 (1997);
Notesco G., Bar-Nun A., Icarus 126, 336 (1997).
15
Spencer J. R., Calvin W. M., Person J., J. Geophys. Res. 100, 19049 (1995);
Calvin W. M., Johnson R. E., Spencer J. R., Geophys. Res. Lett. 23, 673 (1996);
Noll K. S., Johnson R. E., Lane A. L., Domingue D. L., Weaver H. A., Science 273, 341 (1996).
16
A. H. Delsemme, in Comets, L. L. Wilkening, Ed. (Univ. of Arizona Press, Tucson, 1982), pp. 85–130.
17
Whittet D. C. B., et al., Astron. Astrophys. 315, L357 (1996).
18
Blake D., Allamandola L., Sandford S., Hudgins D., Freund F., Science 254, 548 (1991).
19
V. C. Farmer, The Infrared Spectra of Minerals (Mineralogical Society, London, 1974);
Farrell E. F., Newnham R. E., Am. Mineral. 52, 380 (1967);
Wood D. L., Nassau K., J. Chem. Phys. 47, 2220 (1967).
20
Cruikshank D. P., et al., Icarus 94, 345 (1991).
21
The initial gas mixtures are as follows: tholin 1, 50% CH4 and 50% NH3, plus small amounts of H2O; tholin 3, 9% CH4 and 91% N2; and tholin 4, 90% N2 and 10% CH4.
22
For a description of the chemical analysis, see
McDonald G. D., Khare B. N., Thompson W. R., Sagan C., Icarus 94, 354 (1991).
23
At 150 K, cyanogen is a solid with a vapor pressure <0.1 mbar, almost identical to the behavior of SO2.
24
Sandford S. A., Allamandola L. J., Icarus 76, 201 (1988).
25
Delitsky M. L., Lane A. L., J. Geophys. Res. 102, 16385 (1997).
26
N-Butyl sulfonal chloride (n-C4H9SO2Cl) and N-nitroso piperidine (C5H10N2O). Spectra are from (10).
27
Smythe W. D., Nelson R. M., Nash D. B., Nature 280, 766 (1979).
28
F. P. Fanale, R. H. Brown, D. P. Cruikshank, R. N. Clark, ibid., p. 761.
29
Noll K. S., Johnson R. E., McGrath M. A., Caldwell J. J., Geophys. Res. Lett. 24, 1139 (1997).
30
J. L. Bishop, C. M. Pieters, T. Hiroi, Meteoritics Planet. Sci. 32, A14 (1997).
31
S. G. Warren, Appl. Opt. 25, 2650 (1986).
32
Falk M., J. Chem. Phys. 86, 560 (1987).
33
We acknowledge the use of the forthcoming U.S. Geological Survey 0.2-150 μm spectral library to be released by R.N.C. We thank D. Cruikshank for providing his published tholin spectra in digital form and D. Stevenson, J. Lunine, and many other colleagues for helpful discussions.
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Science
Volume 278 | Issue 5336
10 October 1997
10 October 1997
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Received: 16 June 1997
Accepted: 2 September 1997
Published in print: 10 October 1997
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