The universe was once considered to be infinite and endless. Billions of galaxies each having trillions of stars, some of whom have planets of their own made scientists think about the possibilities of Earth like planets existing in solar systems much like ours. The discovery that the universe is, in fact, finite, albeit expanding, hasn’t changed this. The very thought of other intelligent life forms existing elsewhere in the universe sends minds and imaginations racing. Extra-terrestrial life has been the subject of many a Hollywood movies and sci-fi books.

In the world of Giordano Bruno – “There are countless suns and countless Earths all rotating around their suns in exactly the same way as the seven planets of our system. We see only the suns because they are the largest bodies and are luminous, but their planets remain invisible to us because they are smaller and non-luminous. The countless worlds in the universe are no worse and no less inhabited than our Earth.”

Although the concept of life on other planets stirs a great deal of enthusiasm among the modern day people, Bruno was burnt at the stake by his colleagues in 1600 for even making this suggestion! In reality, the truth behind his statement signifies the challenge that astronomers today face while hunting for life or even other solar systems. The very size and expanse of the universe which raises the possibility of extra-terrestrial life makes it terribly difficult to look for other solar systems, despite all our modern technology and equipment.

Not only is it difficult to spot planets that may be revolving around known stars but it is even tougher to observe them. To add to this, just like the Earth, all planets would have to go through the physical changes that it went through since its formation till it finally cooled down and became suitable for the development of organic life. Finding an Earth-like planet is a tough task indeed.