The first exoplanet to be spotted, orbiting a star like our own Sun, was discovered back in 1995. Since that historic finding almost a generation ago, exoplanet discoveries have poured in at a breathtaking pace and–as of this writing–more than 1,000 remote worlds circling distant stars have been confirmed. The search for a habitable planet, like our own world, remains the Holy Grail of dedicated planet-hunters. In November 2013, astronomers from the University of California at Berkeley and the University of Hawaii, Manoa, reported their estimation that one in five Sun-like stars have Earth-size planets with surface temperatures friendly to the evolution of life. Given that about 20 percent of stars are mcm shoulder bag Sun-like, this amounts to several tens of billions of potentially habitable Earth-size exoplanets in our Milky Way Galaxy–alone!
“When you look up at the thousands of stars in the night sky, the nearest Sun-like star with an Earth-size planet in its habitable zone is probably only 12 light-years away and can be seen with the naked eye. That is amazing,” commented Berkeley graduate student Erik Petigura in a November 4, 2013 University of California, Berkeley, Press Release. Mr. Petigura led the analysis of data derived from NASA’s Kepler Space Telescope that arrived at this impressive number of potentially habitable mcm purse Earth-like worlds. Kepler is now unfortunately crippled, with its four-year mission at an untimely end. Nevertheless, it still managed to provide enough precious data to answer its primary research question: How many of the 200 billion stars in our Galaxy could potentially host habitable planets?
“It’s been nearly 20 years since the discovery of the first extrasolar planet around a normal star. Since then, we have learned that most stars have planets of some size orbiting them, and that Earth-size planets are relatively common in close-in orbits that are too hot for life,” explained Dr. Andrew Howard in the November 4, 2013 Berkeley Press Release. Dr. Howard, a former Berkeley post-doctoral fellow is now on the faculty of the Institute for Astronomy at the University of Hawaii. “With this cheap mcm backpack result, we’ve come home, in a sense, by showing that planets like our Earth are relatively common throughout the Milky Way Galaxy,” he added.
This plethora of planets far exceeds what astronomers dreamed of before NASA launched Kepler in 2009. The telescope, which is in orbit around the Sun, discovers exoplanets by looking for them as they “transit”–that is, pass in front of–the brilliant, fiery faces of their stellar parents. This transit causes a brief dimming of the parent star’s light. “When I first started working with Kepler right before launch, I thought there would be maybe a thousand planets that Kepler would find,” said Dr. Jason Rowe at a November 4, 2013 press conference, held at the Kepler Science Conference in Moffett Field, California. Dr. Rowe is an astronomer at the SETI (Search for Extraterrestrial Intelligence) Institute in Mountain View, California.