Skip to Main content Skip to Navigation
Journal articles

The detached haze layer in Titan's mesosphere

Abstract : By comparing observations from the Cassini imaging system, UV spectrometer, and Huygens atmospheric structure instrument, we determine an apparent radius of not, vert, similar40 nm, an imaginary index <0.3 at 187.5 nm and a number density of not, vert, similar30 particles cm−3 for the detached haze layer at 520 km in Titan's mesosphere. We point out that the detached haze layer is coincident with a local maximum in the measured temperature profile and show that the temperature maximum is caused by absorption of sunlight in the detached haze layer. This rules out condensation as the source of the layer. The derived particle size is in good agreement with that estimated for the size of the monomers in the aggregate particles that make up the main haze layer. Calculations of the sedimentation velocity of the haze particles coupled with the derived number density imply a mass flux View the MathML source, which is approximately equal to the mass flux required to explain the main haze layer. Because the aerosol size and mass flux derived for the detached layer agree with those determined for the main layer, we suggest that the main haze layer in Titan's stratosphere is formed primarily by sedimentation and coagulation of particles in the detached layer. This implies that high-energy radical and ion chemistry in the thermosphere is the main source of haze on Titan.
Document type :
Journal articles
Complete list of metadatas

https://hal-insu.archives-ouvertes.fr/insu-00385143
Contributor : Béatrice Pibaret-Bourdon <>
Submitted on : Monday, May 18, 2009 - 2:35:57 PM
Last modification on : Friday, September 25, 2020 - 11:20:12 AM

Identifiers

Collections

INSU | CNRS | OSUG | UGA

Citation

Panayotis Lavvas, R. V. Yelle, V. Vuitton. The detached haze layer in Titan's mesosphere. Icarus, Elsevier, 2009, 201 (issue 2), pp.626-633. ⟨10.1016/j.icarus.2009.01.004⟩. ⟨insu-00385143⟩

Share

Metrics

Record views

413