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ToSeek
2002-Feb-12, 02:31 PM
Taking to the air on Titan (http://www.space.com/scienceastronomy/solarsystem/titan_blimp_020212.html)

The Curtmudgeon
2002-Feb-12, 07:54 PM
The artist doesn't seem to have put a gondola beneath the blimp, just a "training wheel" /phpBB/images/smiles/icon_smile.gif . Surely the engineers in the 'Zeppelin von Titan' won't be living up amongst the gas cells? Hard to see where you're going that way....

Okay, okay, I know about using instruments for indirect viewing. It just seems to detract, somehow, from the zeppelinity of the thing. /phpBB/images/smiles/icon_razz.gif

The (will we get Nazi spies/saboteurs with this one?) Curtmudgeon

Chip
2002-Feb-12, 08:09 PM
On 2002-02-12 09:31, ToSeek wrote:
Taking to the air on Titan (http://www.space.com/scienceastronomy/solarsystem/titan_blimp_020212.html)


Interesting article and really cool paintings (when enlarged.)

At that distance, when they eventually move to lower altitudes, (or just to react quickly and trim the craft in a headwind,) the Earth-to-Titan radio time lag is much too long for a "look out - avoid that cliff!" command. So the on-board flight and navigation package should be something to see too!

Kaptain K
2002-Feb-12, 11:19 PM
The artist doesn't seem to have put a gondola beneath the blimp...
Surely, you are aware that this is an unmanned mission being discussed.

Jigsaw
2002-Feb-13, 02:32 AM
I think that is just the most adorable little thing (I LOVE the bicycle wheel), and I WANT one. Any ideas on how much one would cost, if you could get one? /phpBB/images/smiles/icon_biggrin.gif

I foresee the "expensive adult toy" market that didn't open up for the Segway, opening up for these. It's only 40 feet long, you could park it in a two-car garage.

[Not completely serious, but hey, I didn't see Velcro walls coming, either]

<font size=-1>[ This Message was edited by: Jigsaw on 2002-02-12 21:33 ]</font>

Bob S.
2002-Feb-13, 03:14 PM
Re: Titan

The article at http://www.space.com/scienceastronomy/solarsystem/titan_blimp_020212.html says that
"'Titan has a density about four times that of Earth's surface atmosphere. That makes it ideal for floating balloons,' Jones said. 'Any balloon on Earth of a given size would carry four times the payload on Titan,' he said."

However, from http://www.seds.org/billa/tnp/titan.html we read that
"Alone of all the satellites in the solar system, Titan has a significant atmosphere. At the surface, its pressure is more than 1.5 bar (50% higher than Earth's)."

Which is correct? It's been a while since my physics class (let's see, PV=nRT, cross multiply and carry the 1...), but I thought there was a linear relationship between pressure and density. Is the pressure 50% greater or is the pressure 300% greater? And should someone inform the designers of this dirigible?

ToSeek
2002-Feb-13, 03:37 PM
On 2002-02-13 10:14, Bob S. wrote:
but I thought there was a linear relationship between pressure and density. Is the pressure 50% greater or is the pressure 300% greater? And should someone inform the designers of this dirigible?


JPL says 60% greater (http://www.jpl.nasa.gov/cassini/Science/titan_what.html)

Others can do the math, but wouldn't the pressure depend on both the density and the gravity? Since Titan is smaller than the Earth, with less gravitational pull, wouldn't it take a greater density to create the same pressure?

ToSeek
2002-Feb-13, 03:49 PM
Some research reveals:

Earth density 1.224 kg/m^3 (http://wright.grc.nasa.gov/WWW/K-12/airplane/atmosi.html)

Titan density 5.38 kg/m^3 (http://www.astro.uni-bonn.de/~dwe/dweid/node10.html)

(Both at surface level.)

_________________
"... to strive, to seek, to find, and not to yield." - Tennyson, Ulysses

<font size=-1>[ This Message was edited by: ToSeek on 2002-02-13 10:50 ]</font>

AstroMike
2002-Feb-13, 06:50 PM
Interesting. I think a blimp on Titan could work. /phpBB/images/smiles/icon_smile.gif

_________________
"The contemplation of celestial things will make man both speak and think more sublimely and magnificently when he descends to human affairs." -Marcus Cicero

<font size=-1>[ This Message was edited by: AstroMike on 2002-02-13 13:51 ]</font>

The Curtmudgeon
2002-Feb-14, 12:27 AM
On 2002-02-12 18:19, Kaptain K wrote:
Surely, you are aware that this is an unmanned mission being discussed.

Nope, that flew /phpBB/images/smiles/icon_smile.gif right past me. I admit that I didn't take the time to really read the article, I just look at the pretty pictoors. /phpBB/images/smiles/icon_lol.gif

The (aw, I wanted to volunteer!) Curtmudgeon