TiME Options

[rlorenz]

Ahoy mateys!

NASA announces Discovery mission selection for Phase A.

Titan Mare Explorer (TiME) is among them. Har!

[punkboi]

I hope TiME gets chosen in 2016. Outer Planet mission > Inner Planet mission

[SFJCody]

I also prefer TiME to the other candidates. METNET can do some Martian geophysical studies and Rosetta/Philae can investigate a comet nucleus. But when's the next chance we'll get to see Titan up close other than this?


Edit: Oops, I forgot METNET was 100% meteorological! For some reason I thought it had a few geophysical instruments as well.

[Juramike]

But when's the next chance we'll get to see Titan up close other than this?

The real beauty of TiMe is that it's instrument package and environment would be perfectly scientifically complementary (synergistic with) all the other currently proposed Titan missions (baloon, JET, AVIATR airplane, future orbiter, etc.)

So if TiME is selected, it shouldn't hurt the chances of other proposed Titan missions from a purely scientific viewpoint.

[tfisher]

I agree: of the three announced candidate missions, TiME really excites the imagination. I expect the images we get back would be pretty underwhelming : I picture something like the myopic postage stamps from the Huygens landing, except with the only visible scenery being a few ripples on a calm lake surface. But the idea of going to such a distant, alien location, and exploring in a way that has never been done before... That is exciting. This mission is about Exploration in the truest sense. I grew up thinking about space from the Star Trek perspective: "to explore strange new worlds, to seek out new life and new civilizations, to boldly go where no man has gone before." That is exactly what the TiME mission sounds like to me Well, minus the new civilizations, and probably [thought not quite certainly!] minus the new life forms. But certainly exploration of a strange new world. Contrast to the other mission proposals, which are more mundane planetary science. That is science with a small 's' : filling in details, trying to add a little bit onto the big pile of knowledge. Still interesting stuff, but not nearly so inspirational.

[centsworth_II]

...I expect the images we get back would be pretty underwhelming...

The descent images should be fantastic! Imagine seeing the shoreline in detail as the probe lands! Also, I'm thinking that eventually the floating probe may be blown onto shore. Hopefully the camera will have remained clear enough to get a good look. That's one thing I worry about, windblown and splashed stuff coating the optics.

[tfisher]

Does anyone know what liquid methane/ethane is like at Titan surface temperatures? Is the picture we should have in mind like rubbing alcohol, or gasoline, or motor oil? Maple syrup? Molasses?

[Juramike]

Does anyone know what liquid methane/ethane is like at Titan surface temperatures? Is the picture we should have in mind like rubbing alcohol, or gasoline, or motor oil? Maple syrup? Molasses?

Gasoline. Not as viscous as water, even at those temperatures. And definitely not as "clingy" as water on glass. Any splashes of liquid on the lenses should creep right off. Not sure about any residual materials, however. But that's one of the reasons TiME is such an exciting mission: just what other things are in those lakes, anyway?

[rlorenz]

Gasoline. Not as viscous as water, even at those temperatures.

Actually, Mike, can be a little more viscous than water if it is ethane-rich.
Maybe even double the viscosity of water if Cordier's model composition
with several per cent propane and butane dissolved in is anywhere close.
see http://www.lpl.arizona.edu/~rlorenz/viscositywaves.pdf

[Juramike]

[The lake mixture] can be a little more viscous than water if it is ethane-rich.

Wow! The estimated viscosity of ethane compared to methane is completely counterintuitive. I wonder what the reason is? I'da thought that it was only intermolecular interactions via dispersion forces, and that one saturated C-H electron cloud would look like another. Off the top of my head, at those low temperatures I'd also guess that the two CH3 groups would be gauche to each other (hindered rotation), negating any hyperconjugation and thus increased polarization of the molecular orbitals.

(Note that N2 is not viscous - likely due to intermolecular lone pair repulsion).

Is it a size thing?

[jasedm]

the two CH3 groups would be gauche to each other (hindered rotation), negating any hyperconjugation and thus increased polarization of the molecular orbitals.

Just what I was going to say Mike......

Very exciting news about the proposal.

Re: pictures of the lake surface, artists renderings I've seen show what looks like a light source - enough perhaps with the available power to be able to get some some good images within a metre or two of the craft?