Titan, the largest of Saturn’s lunar offspring, is currently at the centre of one of the largest debates in the history of astrobiology. It is the only natural satellite in the Solar System to have a dense atmosphere, and the only other object apart from Earth, which has stable bodies of surface liquid, making it the only other candidate for supporting life. Titan was discovered back in the 17th century by a Dutch astronomer, but the debate over its ability to sustain life has only just arisen since the Cassini spacecraft uncovered the moon’s surface using radiophotography from orbit. These photos, as well as other measurements from the craft, revealed numerous liquid methane lakes, cryovolcanoes and river beds; all three a tell-tale sign of life. Since then, scientists from across the world have been racing to present the first paper on potentially the most significant discovery in the history of mankind: extra-terrestrial life.
After endless analysis of the chemicals that make up Titan’s atmosphere, scientists have now uncovered evidence that alien life exists on Saturn’s moon. The first paper, published by NASA, showed that hydrogen gas that circulated through the plant’s atmosphere, disappeared at the surface. It was implied by scientists that the lack of the chemical was due to consumption by life. One of NASA’s astrobiologists, Chris McKay said: “We suggested hydrogen consumption because it’s the obvious gas for life to consume on Titan, similar to the way we consume oxygen on Earth.” It has been the study of Titan’s atmosphere that has lead the research thus far, as scientists search continuously for more pieces of the puzzle that is alien life. What most scientists find so exciting about this research is the prospect of discovering life that has different building blocks to our own. Life on Titan would represent a hydro-carbon based life form rather than the water based life situated on Earth.
However, not all scientists believe that this moon holds the necessities for life and believe the research is nothing but a dead-end. Professor John Zarnecki, of the Open University, noted that although the basic ingredients for life are still there - heat is still needed to kick-start the process. There are also scientists who warn there could be other reasons for the findings in the atmosphere. Another question that has been raised about the theories of NASA’s research team, is that as the temperature on the surface is so low, it is far more likely that life forms would exist deep in its hydrocarbon oceans, closer to the warm(ish) conditions of the planet’s core. There are bacteria found on earth that can survive under extreme pressures and temperatures and it would be species similar to these in their resilience that might be lurking at the bottom of these mysterious oceans. It is clear by the divide in the scientific community that the formula for life is still as elusive as it was two thousand years ago in the mind of Greek Astronomer Cleomedes.
What even the sceptics can’t deny is that in four billion years’ time, when the Sun swells into a red giant, Titan could become a prime candidate for life, as the temperature on the moon rises and the chemical reactions of life begin to speed up to the point that everything that has been spoken about, becomes possible. But this is a rather long way in the future and it would be nigh on impossible to predict what would happen to the planet and its atmosphere.
There is currently no project at any space agency in the world, which is devoted to actually proving the existence of life on Titan. But it is expected that as the Chinese Space Agency expands, a mission will come about where Titan will be brought a little closer to home. As Titan is so far from our planet, a manned mission to the ice moon is not at all feasible, thus exploration will be limited to probes and un-manned crafts. Again the probability of further exploration of Titan decreases, as the search would primarily include diving into its vast and treacherous lakes; this would include using technology far from the grasp of modern day man. It is left up to the governments of the world whether or not they want to devote the manpower, funds and time into exploring this enigmatic moon.