Why Did Astronomers Think There Might Be Life On Mars?

Mars is considered to be a sort of twin of our own planet earth. It is the next planet beyond the earth in distance from the sun. It has a day that is almost equal in length to our day here on earth.

In observing Mars, astronomers have noticed certain things that indicate a form of life may be possible there. First of all, Mars has seasons like the earth. In fact, as the seasons change on Mars, there seem to be changes on its surface. Astronomers also believe that there is that there is at least a small amount of water vapour in the atmosphere of Mars, and this would be helpful in supporting life. In 1887 an Italian astronomer, Giovanni Schiaparelli reported seeing markings on the surface of Mars that resembled canals.

In 1976 two American Viking space probes landed on the surface of Mars. The instruments in the space probes searched the surrounding soil for signs of life and radioed their results back to earth. If life does exist on Mars it would be a very simple form of life.