Our Milky Way Galaxy may be home to 2 billion planets that have the right conditions to support life. These planets have the correct temperature for liquid water. While no one knows what alien life would look like, if it is anything like life on earth, it would need water to survive. The possibility of liquid water depends on a planet’s distance from the nearest star. Too close and water evaporates; too far away and water freezes. Scientists have also looked at the effects of clouds on planet temperature. This has increased the estimate of habitable planets to 2 billion. This is only the number of habitable planets in the Milky Way Galaxy, which is just one of an estimated 100 to 200 billion galaxies in the universe.
The Martians were giants with the strength of twenty men. When they attacked Earth, it looked like all was lost. The Martians were just too strong. Fortunately, their immune systems were not strong enough to fight off common earthly bacteria. Edison’s Conquest of Mars is a science fiction story written in 1898 by Garret Putman Serviss. The story starts as the war for Earth ends, and humans chase the aliens back to their home on Mars.