Humans have had a fascination with Mars for thousands of years. Because Mars occupies the mild region of the Solar System and is near a planet where life took hold, we often ask, "Might life have arisen on Mars also? Might there be life, perhaps in the form of little green men or even microbes, there today?" We don't know the answer to these questions yet, but we are already on our way. As we explore "our Mars" - sending unmanned vehicles and, perhaps one day, our own astronauts - we learn more about our Solar System and our planetary neighbour. The greatest discovery, however, remains to be made. If even one microbe is found on Mars, it will confirm that there is life elsewhere - that we are not alone. The cosmic context for life on Earth will be set as being one place among many that harbour life. It will confirm our cosmic origins and destiny.
