This month's guest panelist, Sanjoy Som, received his PhD in Planetary Sciences with a certificate in Astrobiology from the University of Washington. He currently works with NASA in a field he calls "Atmospheric Geology". He brings that expertise to our forums to explain to everyone some more of the details of what Titan's surface will look like.
You can read more about Sanjoy's work with NASA here: http://spacescience.arc.nasa.gov/staff/sanjoy-som
Titan is a “planet-like moon” that has many similarities (and differences!) with Earth. These similarities make it fun to think realistically about what one would see if standing on the surface, because we have knowledge of our home planet to guide our imagination. But would we see anything? After all, Titan only receives about 1% of the light than Earth does and is shrouded in an organic haze sheathed by a dense atmosphere of nitrogen thicker than Earth’s. As it turns out, the (smoggy) visibility wouldn’t be too bad once you got used it, as the surface luminosity would be about 300 times brighter than the brightness on Earth at night under a full moon.
At the surface then, human colonists would likely see a butterscotch sky with a few low elevation hills and mountain ranges in the horizon. Plains would dominate the landscape, with dune fields being a common sight. Perhaps the most striking elements of Titan are the lakes of liquid methane and ethane that Dr. Jacob Haqq-Misra introduced in an earlier post on this forum. Many of those lakes are fed by rivers. Standing on one of those mountains, witnessing such a river flowing down towards the plains would be quite a sight. Some of these are not little streams either. Indeed, a river a third of a mile wide has been reported. The highest peak on Titan reaches 1.2 miles in elevation and is located in the Xanadu region within the Mithrim Montes range (yes, that is named after Tolkien – a theme taken for all of Titan’s mountains). Xanadu is recognizable because it is a particularly bright patch the size of Australia on Titan’s surface, likely due to an abundance of reflective ice. Ice on Titan, due to the extremely cold temperatures, would be hard as rock. Mountain ranges on Titan, likely made out mostly of water ice rather than rock, are not formed the same as they do on Earth. On Titan, it is thought that it is the slow shrinking (due to cooling) of the moon that causes the mountain ranges. Think of a shriveling raisin.
Titan’s lakes tend to be relatively shallow, although we don’t know for sure, as the radar instrument on board the Cassini spacecraft currently orbiting Saturn can only probe to a depth of about 26 feet. Ontario Lacus for example, located near the south pole, is roughly 20% smaller than one of the Great Lakes on Earth: Lake Ontario. While Lake Ontario has an average depth of about 280 ft, Ontario Lacus on Titan has an average depth of about 10 ft. Ligeia Mare located in the northern hemisphere is larger than Lake Superior and has a depth greater than the 26 ft maximum that the Cassini instruments can measure. The surfaces of those lakes are likely very smooth. The surface variation of Ontario Lacus for example, was measured not to exceed 1/9th of an inch! This could mean two things: either the winds were minimal when the measurements were taken, on the liquid is unexpectedly viscous.
Titan would be an easy moon to explore for colonists. Indeed, the extremely low gravity (0.14g - less than the Earth’s moon) coupled with the thick atmosphere – 7 times the density of Earth’s atmosphere), would, according to Robert Zubrin in his book “Entering Space: Creating a Spacefairing Civilization”, allow colonists to strap on wings and take to the air. Now let THAT make your imagination go wild!