A team of NASA administrators and university researchers announced the possibility of past life on the planet Mars.
Last August, the team, led by David McKay of NASA, reported the first identification of organic compounds in a Martian meteorite. They also found textural and mineralogical signs of past life within the pores and fractures of the meteorite they called Allan Hills 84001 (ALH84001). The meteorite weighed 1.9 kilograms and was about the size of a big potato.
ALH84001 is believed to be a rock from Mars which was thrown into space when an asteroid crashed into the the red planet's surface 16 million years ago. The meteor probably drifted into solar orbit for millions of years, and fell into Earth's orbit and landed on an ice field in Antarctica 13 thousand years ago. In 1984, scientists discovered the meteor and identified its Martian origins.
The team also showed images of the meteor's interior taken via electron microscope. One of the most prominent images showed a segmented, tubelike, object which represented nanobacteria similiar to those on Earth. Its width was a hundredth of a human hair. Other images showed carbonate globules which are closely associated with fossils of ancient bacteria.
Their primary evidence of early life on Mars was the presence of polycyclic aromatic hydrocarbons (PAHs) among the carbonate globules. PAHs are the first organic molecules ever seen in a Martian rock. A series of tests indicated that the PAHs were indigenous to the rock and not the result of terrestrial contamination. They further concluded that the PAHs were formed through the fossilization of bacteria inside the rock.
Recent findings on Mars also show that the planet once had rivers and lakes. If this is proven, the presence of water is not exclusive to the Earth. These discoveries point out that Mars was like the Earth before. It once had atmospheric and geological conditions that support life.
Consequently, NASA and other space agencies have scheduled a series of space launches to Mars in order to explore the planet more intensively. While these missions are just unmanned probes and landers, they will collect enough data to prepare a manned mission to Mars, hopefully within the first few decades of the next century.
These missions will help scientists confirm their theories about Mars and the Universe as well. Who knows? Maybe we can have a space colony on Mars sooner than we think.
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