But, of course, until life on other worlds is confirmed, this remains speculative.
So, what's new? Recently, NASA has announced the confirmation of 715 new planets, orbiting 305 stars bringing the total planetary count to nearly 1700. There are also several thousand candidate planets awaiting confirmation. Yowza, that's a lot of new ground. Interestingly, as the below chart indicates, most of the newly-confirmed planets are not too distant in size to Earth.
Even more exciting is the discovery of several new planets that occupy the "habitable zone," which is defined as planets that have the right temperature to have liquid water on the surface. Below is an artists depiction of habitable zone worlds, from the Planetary Habitability Laboratory at the University of Puerto Rico at Arecibo, which was recently featured on NASA's Astronomy Picture of the Day. It is also possible, since several of these worlds orbit the same star, that star systems with multiple habitable planets are common.
But, the Kepler data is not the only news. NASA announced a "concept under study" to re-visit Europa, one of Jupiter's moons. Europa, which is slightly smaller than Earth's Moon, is considered to be one of the more likely candidates to harbor extraterrestrial life within the Solar System. Although most of the moon's surface is frozen, a few months ago the Hubble Space telescope detected plumes of water vapor on Europa's surface, and it is believed that there is liquid water beneath the icy crust. The concept of the Europa Clipper is to put a vessel in orbit around the moon to perform detailed instrument analyses. Among the questions is how thick is the ice crust on the surface? Could the giant moon harbor creatures in the oceans of water beneath its surface? I say, let's go fishin'--who knows what will bite? Below is a picture of Europa taken by the Galileo Probe in 1996.
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In closing, I would like to leave you with this quote from Neil deGrasse Tyson.