Skip to main content
Journal cover image

Polycyclic aromatic hydrocarbons in the atmospheres of Titan and Jupiter

Publication ,  Journal Article
Sagan, C; Khare, BN; Thompson, WR; Mcdonald, GD; Wing, MR; Bada, JL; Vo-Dinh, T; Arakawa, ET
Published in: Astrophysical Journal
1993

Polycyclic aromatic hydrocarbons (PAHs) are important components of the interstellar medium and carbonaceous chondrites, but have never been identified in the reducing atmospheres of the outer solar system. Incompletely characterized complex organic solids (tholins) produced by irradiating simulated Titan atmospheres reproduce well the observed UV/visible/IR optical constants of the Titan stratospheric haze. Titan tholin and a tholin generated in a crude simulation of the atmosphere of Jupiter are examined by two-step laser desorption/multiphoton ionization mass spectrometry. A range of two- to four-ring PAHs, some with one to four alkylation sites are identified, with net abundance ∼10-4 g g-1 (grams per gram) of tholins produced. Synchronous fluorescence techniques confirm this detection. Titan tholins have proportionately more one- and two-ring PAHs than do Jupiter tholins, which in turn have more four-ring and larger PAHs. The four-ringed PAH chrysene, prominent in some discussions of interstellar grains, is found in Jupiter tholins. Solid state 13C NMR spectroscopy suggests ≃25% of the total C in both tholins is tied up in aromatic and/or aliphatic alkenes. IR spectra indicate an upper limit in both tholins of ≃6% by mass in benzenes, heterocyclics, and PAHs with more than four rings. Condensed PAHs may contribute at most ∼10% to the observed detached limb haze layers on Titan. As with interstellar PAHs, the synthesis route of planetary PAHs is likely to be via acetylene addition reactions.

Duke Scholars

Published In

Astrophysical Journal

ISSN

0004-637X

Publication Date

1993

Volume

414

Issue

1

Start / End Page

399 / 405

Related Subject Headings

  • Astronomy & Astrophysics
  • 0306 Physical Chemistry (incl. Structural)
  • 0202 Atomic, Molecular, Nuclear, Particle and Plasma Physics
  • 0201 Astronomical and Space Sciences
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Sagan, C., Khare, B. N., Thompson, W. R., Mcdonald, G. D., Wing, M. R., Bada, J. L., … Arakawa, E. T. (1993). Polycyclic aromatic hydrocarbons in the atmospheres of Titan and Jupiter. Astrophysical Journal, 414(1), 399–405.
Sagan, C., B. N. Khare, W. R. Thompson, G. D. Mcdonald, M. R. Wing, J. L. Bada, T. Vo-Dinh, and E. T. Arakawa. “Polycyclic aromatic hydrocarbons in the atmospheres of Titan and Jupiter.” Astrophysical Journal 414, no. 1 (1993): 399–405.
Sagan C, Khare BN, Thompson WR, Mcdonald GD, Wing MR, Bada JL, et al. Polycyclic aromatic hydrocarbons in the atmospheres of Titan and Jupiter. Astrophysical Journal. 1993;414(1):399–405.
Sagan, C., et al. “Polycyclic aromatic hydrocarbons in the atmospheres of Titan and Jupiter.” Astrophysical Journal, vol. 414, no. 1, 1993, pp. 399–405.
Sagan C, Khare BN, Thompson WR, Mcdonald GD, Wing MR, Bada JL, Vo-Dinh T, Arakawa ET. Polycyclic aromatic hydrocarbons in the atmospheres of Titan and Jupiter. Astrophysical Journal. 1993;414(1):399–405.
Journal cover image

Published In

Astrophysical Journal

ISSN

0004-637X

Publication Date

1993

Volume

414

Issue

1

Start / End Page

399 / 405

Related Subject Headings

  • Astronomy & Astrophysics
  • 0306 Physical Chemistry (incl. Structural)
  • 0202 Atomic, Molecular, Nuclear, Particle and Plasma Physics
  • 0201 Astronomical and Space Sciences