For people who are interested in all things beyond Earth, the words methane and titanium go hand in hand. Titan is, after all, the only other world in our solar system where liquid flows over the surface. While trying to understand Titan's meta-cycle, scientists have discovered something else: a bizarre metanis function that wraps halfway around Saturn's greatest moon.
There is a lot of mystery about Titan, and especially about its meta-cycle. Most of what we know about the moon is a result of the Cassini mission. This mission ended in September 2017, but the data is still being investigated.
On Titan, methane in the atmosphere is continuously broken up by the sun's energy. It creates a cloudiness in the atmosphere, which lies on the surface as organic sediments. The thing is, there is no clear source of new methane, so Titan is exhausted by methane in geological time scales.
A team of scientists led by Caitlin Griffith of the University of Arizona attempted to understand the lunar methane cycle. The only obvious source of new methane is the liquid methane lakes and oceans on the surface, although they will eventually be exhausted. Griffith and her team were interested in potential cryovolcans that could exist on the surface of Titan, and if they signaled the presence of underground reservoirs of methane.
However, the team discovered something unexpected: a linear corridor of metanis and bedrock that spans 40% of Titan's surface.
"This icy corridor is enigmatic because it does not correlate with surfaces or measurements of the subsoil," Griffith said. "Given that our study and past work show that Titan is currently not volcanically active, the track's track is probably a past past. We discover this feature on steep slopes but not on all slopes, suggesting that icy corridor is currently eroding, possibly revealing the presence of ice and organic layers. "
The team analyzed tens of thousands of images captured by Cassinis
Synthetic and Infrared Mapping Spectrometer. Titanium is difficult to observe due to its thick, cloudy atmosphere, but Griffith and the other researchers behind the study used a new method to justify the details of some surface properties. They were actually looking for interesting organic materials that accumulate on the surface due to the sun breaking up in atmospheric methane.
Of course, it wouldn't be science if they didn't try to test or validate their own results. They compared their results to what the little Huygens probe saw when it was sent to the surface of the Titan by the Cassini spacecraft. The comparison actually confirmed their results.
"Both Titan and Earth followed various evolutionary paths, and both ended with unique organic rich atmospheres and surfaces," Griffth said. "But it is not clear whether Titan and Earth are common drawings of organically rich bodies or two among many possible organic rich worlds."
As with all things Titan, these results are both convincing and mysterious and seem to answer questions as well as form new ones.
These results are a bit of a sidetrack of the team's goals. They will still study the various organic sediments that accumulate on the surface due to the photolysis of atmospheric methane. They are hoping that the technique they used can also be used in that effort.