Atmospheric Chemistry of Titan Options

[Juramike]

Here is a "Benzene-O-Vision" graphic showing the amount of benzene and phenyl radicals at high altitudes on Titan. This is based on detections of benzene and phenyl radical (which recombined in the sample chamber to make benzene) using the INMS instrument during closest approach. The numbers are normalized to constant pressure altitude, roughly 1000 km.



The data was taken from Table 1 in: Vuitton et al, Journal of Geophysical Research 113 (2008) E05007. "Formation and distribution of benzene on Titan". doi: 10.1029/2007JE002997 [EDIT 5/24/10: Article freely available here] and overlaid on a map of Titan.

The authors mentioned that the errors in these measurements are 20%.

These detections are well above the detached haze layer. Most are at the same sun azimuth angle. (T23 observation had the lowest angle.) Assuming that the temporal difference is minimal (each dot is from a different flyby), there doesn't appear to be an obvious correlation with latitude.

This graphic does show that benzene is present even waaaay up in the thermosphere and ionosphere.

[Juramike]

Very cool!

Here is an EXCEL conditional formatted graphic that shows how the predicted fluxes have varied between one published model and the next. These are all surface height ratios (m.w. and predicted density taken into account) normalized to values from the Krasnopolsky 2009 model. Yellow-orange means it is ballpark same order of magnitude. Dark red shows that the model underpredicts relative to Kransopolsky 2009 by over an order of magnitude, while dark blue shows that the past model overpredicts the Krasnopolsky 2009 by over an order of magnitude.



As yet another example, 1-butene (CH2=CHCH2CH3, m.w. 56, a liquid at Titan temperatures) has some of the greatest variation between all the models.

[rlorenz]

Here is an EXCEL conditional formatted graphic that shows how the predicted fluxes have varied between one published model and the next.

Nice presentation.
It'd be interesting to add in some of the older models (Yung, Lara etc.)

btw it is possible that the number of significant digits displayed in your spreadsheet
exceeds the level of fidelity of the models, if not the attention span of the reader

[Juramike]

As requested (twice now) here is a comparison of some of the earlier pre-Cassini models with more recent atmospheric model production rates. Again normalized to Krasnopolsky et al., 2009:





(Done using conditional formatting in EXCEL, most literature models only have 2 significant figures listed. Extra digits displayed after normalization to set conditional formatting.)