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24

Titan "lakes": Published Open Access in Science: Radar Evidence for Liquid Surfaces on Titan Campbell, D. B., Black, G. J., Carter, L. M., and Ostro, S. J., Science 302, 5644, pp. 431-434, 17 Oct 2003 DOI: 10.1126/science.1088969 This was a really elegant experiment! A continuous, unmodulated, circularly polarized 13 cm wave was broadcast from Arecibo ...


22

The chemistry of Titan's atmosphere is complex, with reactions occurring between carbon dioxide, oxygen, carbon monoxide, hydroxl, and other compounds. This means that carbon dioxide production and destruction takes place through a variety of reactions (Samuelson et al. 1983), some spurred by ultraviolet light from the Sun (and hence photodissociation). In ...


16

Titan is one of Saturn's moons. Titan has a dense atmosphere, at about 1.5 bars. It also seems to have lakes of liquid methane. For a conventional combustion, you would need a good Methane-Oxygen mix. Every combustion is basically an oxidization. Apart from very energetic events, such as SL9 hitting Jupiter, you will need quite a bit of oxygen to get a nice,...


16

One second of googling reveals the whole archive: http://esamultimedia.esa.int/docs/titanraw/index.htm (note you can click onto the strips to inspect them!) The archive depicts the whole decent of the Huygens lander onto Titan, with the first picture being on the ground, and some of them seem to be taken from higher up altitudes, pages 17-27 you can see the ...


15

Surface gravitational acceleration on an object with mass $M$ and radius $R$ is given by $$ g = \frac{GM}{R^2} \propto G\rho R $$ where $\rho \propto M/R^3$ is the density of the object. If one body has smaller surface $g$ than another, it must have smaller density $\rho$, smaller radius $R$, or both. Titan is larger than Earth's Moon, so your observation ...


14

The answer to this is certainly tidal forces, but that doesn't explain the exact mechanism for how tidal forces result in tidal locking, i.e., an orbiting body showing the same face to the central body as it orbits due to the rotation rate and revolution rate being equal. I'll describe this mechanism using the Earth-Moon system so I can be specific, but it ...


12

It did not detect methane lakes. It found that Titan was shiny (in radar terms): that is, the reflections were from a smooth surface rather than a rough one, and at the same time not very intense. As a result (quoting the 2003 New Scientist article Radar reveals Titan's methane lakes linked in one of the comments to your question), “some researchers ...


9

From your first link, the definition is: "The circumstellar habitable zone (CHZ), or simply the habitable zone, is the range of orbits around a star within which a planetary surface can support liquid water given sufficient atmospheric pressure.[1][2][3][4][5] The bounds of the CHZ are based on Earth's position in the Solar System and the amount of ...


7

Mars and Titan differ markedly in distance from the Sun, composition, and possibly geological activity. Titan is about 6.3 times as remote from the Sun as is Mars, which means Titan receives about 1/40th solar radiation that Mars does, with about the same reduction in solar wind. Mars' small size coupled with its much closer proximity to the Sun allowed the ...


5

I wonder if this would be better for worldbuilding or space travel, but I can touch on the basics. You'd need oxygen and protection from the cold, but a space suit on Titan would be less restrictive, not more restrictive than the ones used on the Moon. The pressure isn't too much, so that actually helps and cold temperature is much easier to protect from ...


5

It's not really known why only Titan has a thick atmosphere while moons like Ganymede don't. One thought is that temperatures may have been too high (well above ~40K) in the Jovian subnebula of our solar system due to the greater gravitational potential energy release, mass, and proximity to the Sun, greatly reducing the $NH_{3}$-hydrate inventory accreted ...


5

This question is little different from asking why, if the Sun is a ball of Hydrogen, it hasn't already exploded (or burned out). It is difficult for me to take it seriously. But I'll try. Methane and Oxygen are gases and will react at room temperature and pressure in certain concentration ranges and when exposed to a spark (or other high energy density ...


5

A lot - from this space.com article: Saturn's moon Titan may be worlds away from Earth, but the two bodies have some characteristics in common: Wind, rain, volcanoes, tectonics and other Earth-like processes all sculpt features on Titan, but act in an environment more frigid than Antarctica. The article goes on to say that while Titan has these earth ...


5

Discovery of Titan, 1655: Unknown diameter. Dollfus, 1970: 4,850$\pm$300km (1). Measured by Filar micrometer (2) and diskmeter / double-image micrometer (3). (Apparently a summary of earlier measurements, currently trying to find print copy) NASA SP-340, 1974: Summary of above techniques, propose settling on 5,000km diameter until it can be measured by ...


5

There is nowhere in the solar system except for parts of Earth where humans have any hope of surviving without heavy technological support. There is next to no free oxygen anywhere, nowhere has a surface whose temperature remains in a range we can tolerate (generously let's say 230-320K) and nowhere has liquid water on the surface. So, at a minimum, we will ...


4

Titan is roughly ten times more massive than Pluto or Eris, the most massive known Kuiper Belt objects (KBOs). (Titan is in fact more massive than any other moon in the Solar System except Ganymede.) It would be a rather strange coincidence if the object that was by far the most massive of the KBOs was in orbit around Saturn, well interior to the Kuiper Belt....


4

It means that Titan has weather (driven by methane rather than water) and that it's weather changes with the seasons. Cassini has been observing Titan for almost half of a Titan year, which is 29.457 times longer than is our year. Titan's weather patterns (where it's cloudy, where it rains) has visibly changed over this time, just as weather patterns here ...


4

It depends on the composition of the atmosphere. In a helium (or other light gas) atmosphere, your voice would have a higher pitch. If the gasses are heavier, your voice drops. The density is also a factor: on Mars, sounds can't be as loud as on Earth. Sound is transmitted as pressure differences, and the largest pressure difference you can get is that ...


4

I would say that your initial observation is flawed, so the question is moot. Huygens landing site, Titan:


4

It's not hard to calculated brightness to distance, but that doesn't take into account cloud cover, which is important for Titan. Just looking at distance first, Titan (based on Saturn's distance) averages 9.6 AU from the sun, or about 1/91st as bright as the sun appears from Earth, assuming equal atmospheres. 1/91st isn't a bright sunny day, but it's ...


4

They might escape from the solar system, if the angles are right. If not, they'll probably wind up in elliptical orbits around the Sun. We'll use a simplifying assumption that the orbits are circular to make the calculations easier; All objects mentioned have orbital eccentricity of less than 0.05. The mean orbital velocity of Jupiter is 13.1 km/s, which ...


3

"since I believe the atmosphere's opacity changes in day time and night time" maybe to a very small factor, somewhere in the upper atmosphere, in the UV-wavelengths where plasma opacities play a role. But not in the optical, where the bulk density of the atmosphere plays a role, wich at 1.6 bar doesn't change much between day and night. Your assertion "So ...


3

I don't know what you're talking about. The only one that seems to have mostly flat rocks is Venus. At least based on what little photographs we have from the surface of Venus. Mars Venus


3

The simple answer is: tidal forces, which are a secondary effect of gravity. In the same way that the Moon causes low and high tides of the oceans here on Earth, the Earth also has a similar effect on the Moon. The force is of the same origin, however far stronger due to the mass of the Earth. These tidal forces cause a torque on the rotation on the Moon ...


3

Titan is believed to have a layer of liquid water under its surface, due to tidal heating of the icy crust. Titan has a surface formed of ices with some hydrocarbon (methane) lakes. The crust of Titan is mostly water ice. Below this, there is a liquid water layer and perhaps more ice and silicate rocks below that. This is described at https://science.nasa....


2

I can give a rough answer to your question and some brief thoughts on the paper, and I invite correction from anyone smarter than me. Your article talks about energy per mole, but energy of production on a daily basis would be a product of solar energy. To produce hydrogen in Titan's atmosphere requires UV light, from this article, UV light of 1600 ...


2

If the pressure were the same as the current pressure on Titan, the planet would be slightly warmer for a while, but not for long. The CO2 would soon be frozen out. It is probable that 4 billion years ago the atmospheres of Venus,Earth,Masrs and Titan were much more similar. A hotter Saturn may have warmed Titan in those days. It probably,like the others, ...


2

As Temperature rises, so would the pressure, this would work immediately, as heat from the sun reaches Titan's surface. The atmospheric escape (and thus, pressure loss, as you describe it) would work on a much longer timescale. We can make a few estimates to determine this timescale: On the most simplified level, the composition if Titan's atmosphere is ...


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