Discovery of Kepler-452b
The news media is currently full of the news of the discovery of Kepler-452b, the planet that is supposed to be Earth’s twin.1,2 It was discovered using the satellite-borne telescope, Kepler, where the exoplanet was found to be at a distance of about 1400 light-years. It has a mass about five times that of Earth and diameter about 60% larger, hence a gravity nearly double that of Earth. It has a year3 about 20 days longer than Earth. That makes it the most similar planet to Earth yet and it is located in the habitable zone around its parent star, which is a G-class star, the same class as our sun.
You see pictures (e.g. Figure 1 here) of a planet with oceans and land masses and some even with green vegetation drawn in. But none of these are actual images of the planet. It is too far away for such a thing, even with man’s best telescopes.
Figure 1. Artist conception of the planet Kepler-452b. Clouds, continents and oceans are included, for which there is no evidence. Credit: NASA
Why all the hype? Well, it is the hope of life being found elsewhere. The way it goes is: find an Earth-sized planet in the habitable zone, called the Goldilocks zone—not too hot, not too cold, but just right—the distance from the parent star where water is in its liquid form—detect the presence of water in its atmosphere and that gives you a good chance of finding life.4 Continue reading
Life in the universe is rare, so rare in fact, I would wager that sentient life is only found on planet Earth. For nearly 50 years the collection of telescopes and scientists under the umbrella name of the Search for Extraterrestrial Intelligence (SETI) have searched among the wavelengths of a myriad stars in search of a radio signal, any signal, from intelligent life. But have they detected any? Apart from detecting the odd microwave oven in their own establishment,1 no is the answer.
Earth 2.0: An artist’s conception depicting of the planet Kepler-452b, the first near-Earth-size world to be found in the habitable zone of star that is similar to our sun. Credit: NASA Ames/JPL-Caltech/T. Pyle
In 2013 Space.com headlines with “Alien Life May Be Rare Across the Universe“2 but on July 23, 2015 NASA announced the discovery of Earth 2.0 with a headline on Space.com of “NASA Finds Closest Earth Twin Yet in Haul of 500 Alien Planets.”3
It is all over the news with a host of pictures of Earth 2.0. But wait, they are only artists’ conceptions.”4 One such drawing is reproduced here.
The report is that NASA found a near twin to Earth named Kepler-452b. It orbits its sun every 385 days, is 60 per cent larger in diameter than Earth, has a mass probably 5 times that of Earth and is located about 1,400 light years away. It’s a big deal! But why? Continue reading