| Life on Titan | | | | that live very deep down and tolerates extreme |
| There are many similarities between the Planet | | | | conditions of heat. |
| Earth and Saturn's giant moon Titan, but on the | | | | There is evidence that Titan has underground |
| Earth, life plays a major part in the various cycles. | | | | reservoirs of liquid water with Ammonia and other |
| Without life on Earth, specifically photosynthetic | | | | compounds dissolved in it. The conditions in these |
| life, we would not have much Oxygen in our | | | | bodies of water are conducive to life similar to |
| atmosphere. On Earth, life also plays an important | | | | the life on Earth. |
| part in the hydrological cycle. | | | | Does Titan Have Life? |
| There may be thriving life on Titan, maintaining | | | | We do not know; most scientists think it is too |
| things like the balance between Methane and the | | | | cold on the surface but we are constantly finding |
| other hydrocarbons and the amount of Nitrogen in | | | | life in more extreme habitats than we had |
| the atmosphere. | | | | suspected a few years ago. Certainly NASA and |
| Methane | | | | other space agencies are hoping to find out. |
| The atmosphere of Titan has more Methane than | | | | How could it have got there? |
| appears likely from the amount of liquid Methane | | | | There are several ways that life could have got |
| on the surface. The most widely accepted | | | | to Titan. The conditions on Titan are similar to |
| explanation of this is that the Methane is being | | | | those postulated for life to evolve from non-living |
| constantly replenished by cold volcanoes. This is | | | | chemicals, so it could have arisen independently of |
| not the only possibility. | | | | life on Earth. Another way is for it to have got |
| Nitrogen | | | | there from the Earth. |
| Both the Earth and Titan have a lot of Nitrogen in | | | | If you do not like the idea of life arising from |
| their atmospheres. On the Earth, there is an | | | | non-living chemicals, the answer is much simpler. If |
| important Nitrogen cycle involving life. Could this | | | | God created life on Earth suitable for our |
| be the same on Titan? | | | | conditions, the Omnipotent Being could have |
| Oxygen | | | | created life on Titan suitable for its conditions. |
| Titan has little or no Oxygen in its atmosphere. If | | | | All the elements necessary for life as we know it |
| any did form, it would tend to react with many of | | | | are present on Titan. What we do not know is if |
| the other components of the atmosphere. Also, | | | | life exists there. |
| Titan gets only about one hundredth of the | | | | Proving Life Does Not Exist |
| concentration of sunlight that the Earth gets. It | | | | If life is found on a moon or planet, then we |
| seems likely that any life on Titan is not | | | | know there is life, but even if you spent a |
| photosynthetic. | | | | hundred years looking and failed to find any life, |
| Photosynthetic Life | | | | you still cannot be sure that no life exists there. |
| On the Earth, Photosynthesis is at the base of | | | | Finding life is proof it is there, but not finding it is |
| the food chain. Plants produce energy containing | | | | not complete proof. |
| compounds; animals depend on plants, or on other | | | | Although most scientists would guess that no life |
| animals that depend on plants, sometimes in a | | | | exists on the surface of Titan, perhaps we are |
| very complicated food chain. | | | | looking at it too much from our own point of |
| Chemotrophic Life | | | | view. We only know about one type of life; that |
| However, in the last 100 years, it has come to be | | | | on Earth. |
| realised that not all life on Earth gets its energy | | | | Consider an astronomer of Titan looking at the |
| from the Sun or from plants as we think of | | | | Earth and deciding if there is life on Earth, with |
| them. There are many thriving ecosystems with | | | | only the life native to Titan as a guide. Perhaps |
| the initial energy being provided by chemical | | | | this astronomer might write: |
| sources. These sources include Methane and other | | | | Is There Life on Earth?(The view of an |
| hydrocarbons. | | | | Astronomer of Titan) |
| We know these are present on Titan. The idea | | | | Although the Planet Earth has all the elements |
| that life in some form exists on the surface of | | | | necessary for life, I think that no conceivable life |
| Titan is not impossible. | | | | could exist in the atmosphere which contains the |
| Underground Life | | | | deadly poisonous gas Oxygen in large quantities, |
| On the Earth, there is an enormous variety of life | | | | quite apart from the extremely high temperature, |
| that lives underground. This includes some bacteria | | | | equal to the temperature of our molten lava. |