Transient clouds in Titan's lower atmosphere

Caitlin Griffith, Tobias Owen, Gary A. Miller, Thomas Geballe

Research output: Contribution to journalArticle

160 Citations (Scopus)

Abstract

The 1980 encounter by the Voyager 1 spacecraft with Titan, Saturn's largest moon, revealed the presence of a thick atmosphere containing nitrogen and methane (1.4 and ~0.05 bar, respectively). Methane was found to be nearly saturated at Titan's tropopause, which, with other considerations, led to the hypothesis that Titan might experience a methane analogue of Earth's vigorous hydrological cycle, with clouds, rain and seas. Yet recent analyses of Voyager data indicate large areas of supersaturated methane, more indicative of dry and stagnant conditions. A resolution to this apparent contradiction requires observations of Titan's lower atmosphere, which was hidden from the Voyager cameras by the photochemical haze (or smog) in Titan's stratosphere. Here we report near-infrared spectroscopic observations of Titan within four narrow spectral windows where the moon's atmosphere is ostensibly transparent. We detect pronounced flux enhancements that indicate the presence of reflective methane condensation clouds in the troposphere. These clouds occur at a relatively low altitude (15 ± 10 km), at low latitudes, and appear to cover ~9 per cent of Titan's disk.

Original languageEnglish (US)
Pages (from-to)575-578
Number of pages4
JournalNature
Volume395
Issue number6702
DOIs
StatePublished - Oct 8 1998
Externally publishedYes

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Saturn
Atmosphere
Methane
Smog
Spacecraft
Rain
Oceans and Seas
Nitrogen

ASJC Scopus subject areas

  • General

Cite this

Griffith, C., Owen, T., Miller, G. A., & Geballe, T. (1998). Transient clouds in Titan's lower atmosphere. Nature, 395(6702), 575-578. https://doi.org/10.1038/26920

Transient clouds in Titan's lower atmosphere. / Griffith, Caitlin; Owen, Tobias; Miller, Gary A.; Geballe, Thomas.

In: Nature, Vol. 395, No. 6702, 08.10.1998, p. 575-578.

Research output: Contribution to journalArticle

Griffith, C, Owen, T, Miller, GA & Geballe, T 1998, 'Transient clouds in Titan's lower atmosphere', Nature, vol. 395, no. 6702, pp. 575-578. https://doi.org/10.1038/26920
Griffith C, Owen T, Miller GA, Geballe T. Transient clouds in Titan's lower atmosphere. Nature. 1998 Oct 8;395(6702):575-578. https://doi.org/10.1038/26920
Griffith, Caitlin ; Owen, Tobias ; Miller, Gary A. ; Geballe, Thomas. / Transient clouds in Titan's lower atmosphere. In: Nature. 1998 ; Vol. 395, No. 6702. pp. 575-578.
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