Published on November 15th, 2011 | by Yellow Magpie1
Titan: Saturn’s Atmospheric Moon
Saturn’s Moon Titan
It stands out. Alone, a one-of-a-kind, unique. The only moon in the Solar System, the only one to have an atmosphere. A colossal satellite compared to our own Moon, Saturn’s moon Titan has for decades defied revealing its true identity. It resides under a haze of orange-tinged cloud. A thick, noxious layer that refuses to let us get even a brief glimpse of what lies underneath.
Until recently we knew virtually nothing about it. A lot can change in a few short years however and Saturn’s moon Titan has finally given up some of its mysteries.
Second only in size to Jupiter’s Ganymede, Saturn’s moon Titan is twice the size of the Moon. The satellite measures 5,100 kilometres (3,200 miles in width) and orbits Saturn from a distance of 1,200,000 kilometres (760,000 miles) taking just under 16 days to complete a trip around the ringed planet.
Titan’s surface is a slightly chilly minus 179 degrees Celsuis (minus 290 degrees Fahrenheit). Although this is almost incomprehensibly cold Saturn’s moon Titan in fact should be much colder. It is its methane that keeps the temperature of its surface warmer than it otherwise would be.
Saturn’s moon Titan was previously considered to be the largest satellite in the Solar System. Its very thick atmosphere makes it appear larger than it is. Even though it is just over 100 kilometres (65 miles) shorter than Ganymede it is still larger than the planet Mercury.
A Strange Kind Of Familiarity
In many ways, Saturn’s moon Titan is much closer to a planet than a typical moon. Of course its most startling aspect is its atmosphere.
Like the Earth, Titan also is geologically active. It is believed that radioactive decay deep beneath the surface is responsible for such geological processes.
Saturn’s moon Titan closely resembles early Earth. Full of methane and organic molecules many scientists believe that the moon is a lot like a lifeless version of our planet with elemental organic building blocks present.
Saturn’s Moon Titan: Lakes Of Methane
After the Cassini mission a long held hypothesis that Saturn’s moon Titan contained seas and lakes of methane was confirmed.
The Kraken Mare is the largest of these bodies with a width of 1,170 kilometres (730 miles). This is roughly the same as the Caspian Sea.
Volcanoes Of Ice
Saturn’s moon Titan is thought to be filled with cryovolcanoes. Instead of lava these volcanoes spew out water and ammonia.
Nevertheless, as of yet there is no conclusive evidence to prove that the cryovolcanoes exist on the satellite.
Two unusual bright spots were discovered by astronomers in Titan’s atmophere in December 2008.
Perhaps the strongest evidence for these types of volcanoes comes from the geology of Saturn’s moon Titan. Despite the assumption that much of the moon’s surface was formed by impacts, this was dispelled when a large mountain range 150 kilometres by 30 kilometres (94 miles by 19 miles) was found.
The Thick Earth-Like Atmosphere
The atmosphere of Saturn’s moon Titan is dense, nearly 1.5 times denser than that of the Earth. It’s atomsphere is also slightly larger than the Earth, despite the fact that Titan is only half as wide as our home planet.
The reason why the atmosphere is so large is due to the low gravity of the moon’s surface allowing it to extend quite a distance.
Apart from the Earth, Saturn’s moon Titan’s atomsphere is the only one to be nitrogen-rich. It is comprised of 98 per cent nitrogen, 1.4 per cent methane and the rest hydrogen.There are also plenty of trace amounts of other compounds. It is thought that one of these compounds, hydrocarbons are thought to be created when the methane gets broken down by the Sun’s ultraviolet rays. It is this process which creates the distinct orange haze.
One of the most intriqing aspects of the atmosphere of Saturn’s moon Titan’s is its methane. By scietist’s estimation Titan should have had all its methane converted into hydrocarbons by the Sun in just 50 million years. This has led to the belief that somhow the moon is replenishing its supply of methane.
Two hypotheses have been proposed to explain this phenomenon The first is that there is a huge store of methane somewhere witin Saturn’s moon Titan itself. The second is that the methane is created by biological organisms.
Organic Matter And Potential Life
Through the Cassini-Huygen’s probe complex organic molecules were discovered on Saturn’s moon Titan’s surface.
Five nucleotide bases, the foundations of DNA and RNA, were produced in an experiment by using the same chemical ingrediants as found on Titan.
If Saturn’s moon Titan contains sub-terrean oceans of water and ammonia it could be possible that microbial life exists on the moon.
Currently, there are plenty of circumstantial indications of potential sources of primitive lifeforms on Saturn’s moon Titan. The apparent disappearance of hydrogen near the surface has led to speculation that methanogenic (organisms that produce methane) microbes consume the hydrogen.
Although such speculations must be taken with a healthy degree of scepticism as possibilities other than life may account for this anomaly.
What Will Happen Titan?
When the Sun eventually starts to near the end of its lifecycle and enters its red giant phase it will expand greatly. This expansion will cause Saturn’s moon Titan to become much warmer than it is is today. Six or more billion years from now – Titan may indeed heat up to above zero temperatures. Furthermore under such conditions complex life could emerge.
Whether or not Saturn’s moon Titan currently harbours primitive microbial life is a question that will probably only be answered when humans set foot on the moon’s surface. Until then we can only speculate. Whatever happens it appears that Titan will always have a special place in the human imagination.
Highly Recommended Reading
Check out Yellow Magpie’s The Planet Saturn: The Ringed Wonder Of The Solar System for more insight into the largest planet in the Solar System.
You may also wish to take a gander at The Solar System And Beyond: A Guide To The Cosmos.
Cosmos is a highly recommended book. It contains large, full-page pictures of the asteroids and writing on the subject by the highly competent author, Giles Sparrow.
For people living in Ireland or the United Kingdom, you can access: Cosmos from here.
For those who live in Canada, you can obtain: Cosmos here.
For Germany: Cosmos.
For France: Cosmos.