There´s no doubt that humanity is at the beginning of a new age of discoveries. Late in the last century we were surprised by the new discovery of distant planets outside the solar system (exoplanets), which opened the possibility to think about other distant civilizations. This took us so far as to think that there could be some sort of life as we know it on Earth. Today we are overwhelmed with astonishment with the discovery of a new exoplanet.
The milestone of this new discovery made by the NASA's Kepler mission relies in which, unlike the previous ones (mostly gas), this exoplanet is made of rock like the Earth.
Although Kepler-10b is an Earth-like rocky planet with a mass 4.6 that of earth and a density of 8.8 grams per cubic centimeter, it´s still far from being able to host life as we know it on Earth, since it is located outside of the area known as habitable, the area in a planetary system where water is likely to be found.
The existence of exoplanets went from being a mere supposition in the tenth century to be a reality, when the first confirmation of the existence of several of them was made in 1992. The discovery of exoplanets has opened the possibility of extraterrestrial life.
The possibility of finding life in other distant planets has been haunting the minds of scientists for over more than a century. It was in 1896 that Nikola Tesla suggested that radio signals could be used to make contact with extraterrestrial life, and it was not until 1974 that the first real attempt was made at the Arecibo Observatory, when a radio signal was sent towards the globular cluster M13.
An exoplanet is one which lies outside of our solar system. As of January 11, 2011, it has been confirmed the discovery of 518 exoplanets, with a lot more planets awaiting to be confirmed as such. Most of these planets are giant gas planets like Jupiter. Several lightweight exoplanets have also been detected, and it is believed that they will soon outnumber giant planets.
With new discoveries to come in this century in the area of cosmology, there´s no doubt that in the future years, this number of rocky exoplanets will outnumber the present ones, and that the possibility of finding a rocky exoplanet with such characteristics as those on planet Earth will open up the likelihood of finding other civilizations living in a world with life as we know it on Earth.