Space is fascinating. Is there life on other planets? In The Moon Stealers series the whole story is based on the possibility of bacteria from another planet arriving within the core of a meteor and growing to become the dominant species on Earth. But how far fetched is this? Well, it’s not impossible…
Mars is the closest planet to ours in the Solar System, and several of the meteorites that have been found on Earth have been identified as pieces of rock from its surface. In addition, it is believed that there was once liquid water available on the planet. Scientists are always exploring the possibility that Mars had life on it at one point and have come up with many reasons which support this theory. Some of the evidence they refer to is the presence of bacteria in meteorites which have crashed into our planet from this neighbouring one.
During the formation of the Solar System, 16 million years ago, some of the planets were devastated and pieces of Mars were cast off in Earth’s direction. In December 1984, one of these meteorites (believed to have crashed here 13,000 years ago) was discovered by a team of explorers in the Antarctic and named Allan Hills 84001. Even though potato-sized and weighing only 4.3 lbs, NASA scientists believe that it is one of the keys to life outside of our atmosphere. Extensive research was done on the rock and in 1996, it was announced that it contained fossils. No further clarification was given to their origin at the time.
Tests on the rock date it back to 4.5 billion years ago, when Mars was formed. Scientists believe that it originated beneath the surface of the planet, which would have had underground water sources at the time, and was extensively smashed by meteorites in the early Solar System. The atmosphere on Mars is rich in carbon dioxide which would have been transferred to its water sources and later deposited in the fractures of rocks as carbonate minerals. The chemical properties in the rock and the fossils were almost identical in nature, proving that they had entered before it left Mars and not after it crashed to the Earth’s surface.
The microscopes that have been used in the more recent studies on the rock are significantly more powerful than those that were used to examine it in 1996, when the fossils were first discovered. NASA also conducted research on the bacteria which yielded the discovery of magnetite crystals, as well as the previously noted carbon discs.
The fossils found are so small that 1000 laid side by side would be the diameter of a dot on a page. Two shapes have so far been observed, egg-shaped and tubular, which are very similar to fossils that have been examined of bacteria that lived on earth’s surface, leading scientists to speculate that life on Mars would have been similar to some of the Earth’s species (if it did exist). NASA continues to research the fossilized bacteria in the hopes that it will help clarify the evolution of life in our Solar System.