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It began as “amazing”. Ended as “badass”. Sorry, English professors.
Today I’m sticking closer to home:
“Arrakis, Dune, Desert Planet.”
- Titan and Arrakis are both yellow-brown desert planets.
- There are thousands of unbroken kilometres of windswept sand dunes on both worlds.
- Both worlds have fantastically exotic ecological processes driven by mysterious factors in the deep desert – Arrakis has sandworms and the spice. Titan has methane.
Even without my dream of an Arrakeen moon replete with Saturian Fremen, Sandworms and the spice Melange, Titan remains a fascinating place.
Titan is simultaneously (trimultaneously?) the first, sixth and twenty-first moon of the gas giant Saturn: The first to be discovered, the sixth in classical astronomical order (Saturn VI) and the twenty-first in order of distance from the parent planet.
Discovered in 1655 by Dutch astronomer Christiaan Huygens, Titan is the largest moon of Saturn and the second-largest moon in the solar system; being larger than the planet Mercury, Titan would be comfortably considered a planet in its own right if it did not orbit the gas giant. But it does and we don’t, unfortunately.
Suspected to exist since 1903 and confirmed in 1944, Titan’s rich, dense and opaque atmosphere that has captured popular imagination and scientific interest with a fervour matched by among the other moons of the outer solar system only by Jupiter’s moons Io and Europa and, recently, another Saturnian moon: Enceladus.
In 1951, Robert A. Heinlein wrote The Puppet Masters, a seminal novel about an invasion of Earth by parasitic aliens from Titan, after their earlier invasion of (a lush and tropical) Venus failed. In 1980, Titan was considered of such scientific import that Voyager 1 was diverted into a close flyby and then up and away from the plane of the ecliptic and any other meaningful flyby of a planetary body. In other words an opportunity to study Titan’s smoggy atmosphere was considered more scientifically important that potential future flybys of of Uranus or Neptune or Pluto.
Titan and its atmosphere were one of the leading objectives of the Cassini-Huygens mission:
The scientific objectives of the Cassini/Huygens mission at Titan are to:
- Determine abundance of atmospheric constituents (including noble gases); establish isotope ratios for abundant elements; constrain scenarios of formation and evolution of Titan and its atmosphere
- Observe vertical and horizontal distributions of trace gases; search for more complex organic molecules; investigate energy sources for atmospheric chemistry; model the photo-chemistry of the stratosphere; study formation and composition of aerosols
- Measure winds and global temperatures; investigate cloud physics, general circulation and seasonal effects in Titan’s atmosphere; search for lightning discharges
- Determine the physical state, topography and the composition of the surface; infer the internal structure of the satellite
- Investigate the upper atmosphere, its ionization, and its role as a source of neutral and ionized material for the magnetosphere of Saturn.
Wordy. Cut it down to a single sentence: Cassini-Huygens was to learn everything there was to learn about the fog-bound moon Titan, its surface, its atmosphere and the hydrological processes replenishing the dense atmospheric smog.
Starting a few years before Cassini-Huygen’s launch in 1997, we had our first peeks under the veil. Infrared examinations by Hubble showed a continent-sized brightly reflective area that we later came to know as the highlands of Xanadu
Later on came the Huygens landing in 2005, a total (so far!) of 71 imaging flybys of the the moon and continued remote imaging from Earth. What these have collectively uncovered is a damp, sandy moon with vast lakes and small seas at both poles, ice-spewing cryovolcanoes, the aforementioned longitudinal sand dunes and active organic chemical processes.
Titan, I salute you.