Ok . This episode is all about atmospheres.
Overall, I’m noticing that the producers seem to be torn between selling Cox’s style, and conveying basic information. It may be my imagination, but there seems to be a whole lot more “soppy” background music to support Cox’s presentation style. His commentary almost lapses into poetry at times, which I personally find hard to listen to.
I also think that they’ve actually disputed their opening points in their latter commentary. Eg: the opening scenes emphasise
the fragility of our ‘Thin Blue Line’ of atmosphere ... then about half way through, Cox is emphasising the ‘sculpting power of weather’, as a
‘huge mass of air moves across the surface’. Almost a contradiction of concepts. Its clear to me they are trying to convey the concept of diversity of environments, but this is not reinforced as a main theme of this episode.
They raise as supporting evidence that
Mars once had a thick atmosphere, by citing a photograph of a Nickel-Iron meteorite found on Mars in Aug 2009. The point being that the meteorite, (if that what it is), could only have remained intact if there was a thick atmosphere to slow it down for landing. I must admit, this is the first time I’ve heard about this. This point raises an interesting question (for me) ... is this the only conclusion possible after reviewing all the evidence ? Can a meteorite fall into a body having the gravity and thin atmosphere of Mars and remain intact ? “Why not ?” is the question I’m left with …
They move onto Titan. Cox talks about
‘lakes of liquid methane’. He refers to Kraken Mare as being composed of liquid. To the best of my research, Kraken Mare is a northern polar sea, identified thus far, as being composed of “hydrocarbons” (imaged by radar).
In June 2008, the Visual and Infrared Mapping Spectrometer on Cassini, confirmed the presence of liquid
ethane beyond doubt, in Ontario Lacus, a southern polar lake. The
latest paper I could find here says:
Quote:
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The chemical composition of the lakes of Titan is still not well determined. Good quality spectral data of the Ontario Lacus have been obtained by the Visual and Infrared Mapping Spectrometer (VIMS) aboard Cassini but the only species that seems firmly identified is C2H6 [Ethane] (Brown et al. 2008); the atmosphere contains so much CH4 [methane] that it is very difficult to detect the surface liquid phase of this molecule even if it is dominant in the lakes.
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The same paper develops a model which results in
a predominance of liquid Ethane by an order of magnitude over liquid Methane.
My point here is that Cox et al, go to great lengths to emphasise that Titan’s lakes are composed of liquid
methane and this seems to not be definitive at all, and the evidence thus far, points to it being composed of predominately, liquid
ethane.
This may seem to be a minor point, but I would have expected better research and more accuracy in major statements made in this episode. My point is that they seem to be more interested in selling Cox’s presentation style, than presenting accurate information and consistent themes.
My 2 cents worth … and all comments welcome.
Cheers