Ever since the dawn of modern astronomy, there is this one question that has troubled the minds of every scientifically inclined person. Is there another earth-like world out there? A planet where life as we know could possibly exist? The sheer vastness of space meant that the answer to this question could never possibly be answered with 100 percent certainty. While the existence of exoplanets -- the ones that are orbiting stars other than the sun -- have been confirmed since the early 90's, most of them could be detected because of their sheer size. Scientists on the lookout for that perfect, earth like (read: earth sized) planet had to wait a bit longer to get their hands full with fresh exoplanet data, because these planets were simply too small to be detected by conventional telescopes.
We needed something way better -- and more powerful.
In 2009, NASA kickstarted the Kepler mission. Kepler is a space telescope observatory specifically designed to discover earth-like planets orbiting other stars. While many doubted if the mission was worth the millions spent to design and launch it, by 2014, there is little doubt left in anyone's mind about the effectiveness of the Kepler mission.
Earlier today, in a press release, NASA has announced that Kepler has detected three new exoplanets that are earth-like and could possibly harbor life. The mission also passed another landmark milestone with the discovery of these three new planets. The Kepler Mission has, in a span of five years, managed to detect over 1,000 new earth-like planets -- all orbiting different kinds of stars in our own galaxy. According to News Australia, since the beginning of the Kepler program, NASA scientists have monitored over 150,000 stars and looked for planets orbiting them. So far, they have managed to find over 4,000 planets, of which at least 1,000 are believed to be very similar to our own Earth in shape, size, and composition.
Meanwhile, the NASA press release adds that the three new 'earth-like' exoplanets were a part of eight other planets that were also discovered recently. These three, however, are the most earth-like in nature and lie in what scientists term the 'habitable zone' in the orbit of the planet's parent star. The habitable zone is that part of the orbit where temperature levels are 'just right' to sustain life as we know it. Scientists have also confirmed that at least two of the newly discovered exoplanets are rocky planets -- like our own Earth.
According to John Grunsfeld, associate administrator of NASA's Science Mission Directorate, every bit of data gathered helps.
"Each result from the planet-hunting Kepler mission's treasure trove of data takes us another step closer to answering the question of whether we are alone in the Universe. The Kepler team and its science community continue to produce impressive results with the data from this venerable explorer."
Meanwhile, Doug Caldwell, SETI Institute Kepler scientist at NASA's Ames Research Center at Moffett Field, California, says the following.
"With each new discovery of these small, possibly rocky worlds, our confidence strengthens in the determination of the true frequency of planets like Earth. The day is on the horizon when we'll know how common temperate, rocky planets like Earth are."
[Image via NASA]