Large-scale, sub-tropical cloud activity near Titan's 1995 equinox

M. T. Lemmon, R. D. Lorenz, Peter Smith, J. J. Caldwell

Research output: Contribution to journalArticle

Abstract

We report observations of Titan using 190 images from the Hubble Space Telescope WFPC2 and NICMOS over 4 oppositions of Titan 1994–1997. Analysis of these images yields maps of surface brightness at 0.67, 0.94, and 1.08 μm that compare well with Cassini data, plus some transient features that are interpreted as large cloud systems. These systems indicate either two clouds covering 2 × 10 6 km 2 (~10% of Titan's observable disk and 2–3% of Titan's surface) in September 1995 or a repeat observation of a single cloud. The clouds are estimated to be upper-tropospheric, with tops between 27 and 39 km altitude. This pre-Cassini observation of prominent cloud activity near 30°N and 40°N shortly before equinox (L s = 177°) mirrors more recent Cassini observations and serves as an important constraint on the seasonal variation of convective activity with latitude on Titan.

Original languageEnglish (US)
Pages (from-to)1-14
Number of pages14
JournalIcarus
Volume331
DOIs
StatePublished - Oct 1 2019

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Titan
annual variations
Hubble Space Telescope
brightness
coverings
seasonal variation
mirrors

Keywords

  • Meteorology
  • Satellites, atmospheres
  • Titan, atmosphere
  • Titan, clouds

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Large-scale, sub-tropical cloud activity near Titan's 1995 equinox. / Lemmon, M. T.; Lorenz, R. D.; Smith, Peter; Caldwell, J. J.

In: Icarus, Vol. 331, 01.10.2019, p. 1-14.

Research output: Contribution to journalArticle

Lemmon, M. T. ; Lorenz, R. D. ; Smith, Peter ; Caldwell, J. J. / Large-scale, sub-tropical cloud activity near Titan's 1995 equinox. In: Icarus. 2019 ; Vol. 331. pp. 1-14.
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