Google has always made sure to celebrate every special affair around the globe. Likewise, it has dedicated its doodle today to NASA`s discovery of seven earth sized exoplanets.In a short, comical animation, the doodle shows NASA`s Spitzer Space Telescope, which revealed the first known system of seven Earth-size planets around a single star. The discovery sets a new record for greatest number of habitable-zone planets found around a single star outside our solar system. All of these seven planets could have liquid water - key to life as we know it - under the right atmospheric conditions, but the chances are highest with the three in the habitable zone.According to NASA, "This discovery could be a significant piece in the puzzle of finding habitable environments, places that are conducive to life.Answering the question `are we alone` is a top science priority and finding so many planets like these for the first time in the habitable zone is a remarkable step forward toward that goal."At about 40 light-years (235 trillion miles) from Earth, the system of planets is relatively close to us, in the constellation Aquarius. Because they are located outside of our solar system, these planets are scientifically known as exoplanets.Source: Business Standard