Sunday, March 27, 2016

These Are Titan's Highest Mountains -- What Lies Beneath?

The trio of ridges on Titan known as Mithrim Montes is home to the hazy Saturnian moon's tallest peak.
Should humankind establish a presence throughout the solar system, future rock climbers and mountaineers might want to put Titan on their list of exploration destinations. Scientists have used precision Cassini observations to measure the heights of the hazy moon’s biggest mountains — and they’re surprisingly high.
Using the NASA spacecraft’s radar, planetary scientists were able to cut through the opaque atmosphere, revealing a rich bounty of geological features, including the moon’s highest peak.
“It’s not only the highest point we’ve found so far on Titan, but we think it’s the highest point we’re likely to find,” said Stephen Wall, deputy lead of the Cassini radar team at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., at the 47th annual Lunar and Planetary Science Conference at The Woodlands, Texas, on Wednesday.
This highest peak comes in at 3,337 meters (or 10,948 feet) and was discovered nestled within 3 mountain ranges known as Mithrim Montes. All of Titan’s highest peaks are around 3,000 meters (10,000 feet) in elevation and clustered around the moon’s equator.
As a comparison, the highest peak on Earth is Mount Everest at 8,848 meters (29,029 feet), so “Titan Mons” certainly isn’t gunning for the record of largest mountain in the solar system. But considering Titan is two and a half times smaller than Earth, having a mountain two and a half times times smaller than the highest mountain on Earth still seems impressive.
(Of course, even Earth doesn’t have the highest mountain in the solar system, that record goes to Mars’ extinct volcano Olympus Mons at a height of 22,000 meters, and it is even dwarfed by a couple of peaks on Venus.)
This radar study was intended to seek out tectonically active regions in Titan’s crust. On Earth, mountains form through tectonic movements (in regions along subduction zones, for example) and through volcanic activity — both sure signs of active geology. Over time, erosion processes wear down mountains and cliffs, providing clues as to their age.
“As explorers, we’re motivated to find the highest or deepest places, partly because it’s exciting. But Titan’s extremes also tell us important things about forces affecting its evolution,” said Jani Radebaugh, a Cassini radar team associate at Brigham Young University in Provo, Utah, and research leader.
Studying Titan’s mountains also reveals exciting clues as to what lies beneath. Titan, like many small bodies throughout the solar system, appears to have a sub-surface ocean of liquid water that acts like the molten mantle on which Earth’s crust floats. However, the bedrock on Titan is likely far softer than rock on Earth, a factor that would limit the height of the moon’s mountain ranges.
“There is lot of value in examining the topography of Titan in a broad, global sense, since it tells us about forces acting on the surface from below as well as above,” said Radebaugh.
Now the researchers hope to further study these mysterious mountain ranges to figure out how they were formed. Are powerful tides from Saturn squeezing the moon’s interior, producing the upthrust to form mountains? Or is there another process at play?
Titan is often cited as a “young Earth analog” — in other words, planetary scientists study the moon, in part, to understand how our planet may have looked before life was sparked on its surface. Although much further away from the sun, Titan possesses many atmospheric processes we have here on Earth, including a methane cycle that produces precipitation (rain), which creates river channels, pooling as vast methane/ethane lakes and “seas.” Other weather processes, including surface winds and fog, have been detected.
Add this amazing soup of atmospheric processes with the fact that Titan’s surface is rich in prebiotic chemicals (the building blocks of life as we know it) and you have what could be viewed as a miniature, albeit colder, Earth bustling with the potential for life.
Although trekking up Titan’s mountains would likely be quite the feat (the 14 percent Earth gravity will help the climb, but the cold toxic atmosphere will ensure you stay sealed inside your spacesuit), understanding their formation and evolution will add yet another chapter to Titan’s early-Earth similarities, not only revealing what mysteries lie beneath the crust, but also the processes that may optimize the moon for life.

Mysterious Activity On Saturn's Moon Titan Baffles Scientists 3/6/16