Some diatomic molecules from comet P/Halley’s UV spectra near spacecraft flybys

  • Max K. Wallis
  • K. S. Krishna Swamy


The abundances of diatomic molecules seen in the UV both give clues to the parent compounds and help unravel the gas and ion mass spectrometry. From IUE spectra of comet Halley, we find upper limits on SH and CS+ column densities, and estimates of probable NO, S2, and SO. In particular, judged from the 226 nm γ-band, NO was relatively abundant at 2–8 1013 cm−2 on March 9–14. The production rate of S2 was around 1 1027 molecules s −1 at that time, but both showed day-to-day variability by 2–3 times.

Key words

gas coma coma molecules UV spectroscopy 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. A’Hearn, M.F., Feldman, P.D., Schleicher, D.G.: 1983, Astrophys. J. 274, L99ADSCrossRefGoogle Scholar
  2. Balsiger, H. et al.: 1986, Nature 321, 330ADSCrossRefGoogle Scholar
  3. Brasseur, G., Simon, P.C.: 1981, J. Geophys. Res. 86, 7343ADSCrossRefGoogle Scholar
  4. Cosmovici, C. B., Ortolani, S.: 1984, Nature 310, 122ADSCrossRefGoogle Scholar
  5. De Almeida, A.S., Singh, P.D.: 1986, Earth, Moon, Planets 36, 117ADSCrossRefGoogle Scholar
  6. Eberhardt, P. et al.: 1986, 20th ESLAB Symp., ESA SP-250, Vol. I, p. 383Google Scholar
  7. Feldman, P.D.: 1982, in Comets, ed. L.L. Wilkening, University of Arizona Press, Tucson, p. 461Google Scholar
  8. Feldman, P. D., A’Hearn, M. F.: 1984, in Ices in the Solar System, eds. J. Klinger et al., Reidel, Dordrecht, p. 453Google Scholar
  9. Festou, M. C. et al.: 1986, Nature 321, 361ADSCrossRefGoogle Scholar
  10. Krasnopolsky, V.A. et al.: 1986, Nature 321, 269ADSCrossRefGoogle Scholar
  11. Krishna Swamy, K. S., Wallis, M.K.: 1986, in New Insights in Astrophysics,ESA SP-243, p. 133Google Scholar
  12. Krishna Swamy, K. S., Wallis, M.K.: 1987, Monthly Notices Roy. Astron Soc. (in press)Google Scholar
  13. Okabe, H.: 1978, Photochemistry of Small Molecules, Wiley, New York, Chap. 5Google Scholar
  14. Rosen, B.: 1970, Selected Constants-Spectroscopic Data Relative to Diatomic Molecules, Pergamon, OxfordGoogle Scholar
  15. Simon, P.C.: 1981, Solar Phys. 74, 273ADSCrossRefGoogle Scholar
  16. Singh, P.D.: 1982, Astron. Astrophys. 108, 369ADSGoogle Scholar
  17. Smith, W.H.: 1969, J. Quant. Spectr. Rad. Transfer. 9, 1191ADSCrossRefGoogle Scholar
  18. Tsuji, M., Obase, H., Nishimura, Y.: 1980, J. Chem. Phys. 73, 2575ADSCrossRefGoogle Scholar
  19. Weaver, H. A., Feldman, P.D., Festou, M. C., A’Hearn, M.F., Keller, H.U.: 1981, Icarus 47, 449ADSCrossRefGoogle Scholar
  20. Woods, T.N., Feldman, P.D., Dymond, K., Sahnow, D.J.: 1986, Nature 324, 436ADSCrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1988

Authors and Affiliations

  • Max K. Wallis
    • 1
  • K. S. Krishna Swamy
    • 2
  1. 1.Department of Applied Mathematics and AstronomyUniversity CollegeCardiffWales,UK
  2. 2.NASA Ames Research CenterMoffett FieldUSA

Personalised recommendations