8 New Planets Discovered; Including Two Of The Most Earth-Like To Date — Brings Total of Earth-Like Planets Discovered To 12 – Two Dozen — Depending On How The Habitable Zone Of A Star Is Defined
Dennis Overbye, writing in today’s (Jan. 7, 2015), New York Times, says that “astronomers announced Tuesday, that they had found 8 new planets, orbiting their stars at distances compatible with liquid water, bringing the total number of potentially habitable planets — in just the right “Goldilocks Zone,” to a dozen or two, depending on how the habitable zone of a star is defined.” “All of these are small, all are potentially habitable,” said Doug Caldwell, of the SETI Institute and NASA Aimes in Seattle, Washington. Of these eight newly discovered planets, “three sit safely within the “habitable zone” of their host star — and one in particular — is rocky, like Earth, as well as only slightly warmer,” wrote Jonathan Webb on the BBC’s January 6, 2015 website. “The three potentially habitable planets join Kepler’s Hall of Fame,” which now boasts eight fascinating planetary prospects,” Mr. Webb wrote. “And, researchers say that the most Earth-like of the new arrivals, known as Kepler 438b, is probably even more similar to our own home than Kepler 186f – which previously looked to be our most likely twin.” Alas, Kepler 438b is 475 light-years away from Earth — an astounding distance that is hard to comprehend.
“NASA’s Kepler spacecraft, now in its fifth year of seeking out the shadows of planets circling other stars, has spotted hundreds — and, more and more of these other worlds look a lot like Earth — rocky balls only slightly larger than our own home, that with the right does of starlight and water, could turn out to be veritable gardens of microbial Eden,” Mr. Overbye wrote. “As the ranks of these planets grow, astronomers are planning the next quest to end cosmic loneliness: gauging which [planets] hold the most promise for life; and, what tools will be needed to learn [more] about them. The planets unveiled on Tuesday, were detected by a group led by Guillermo Torres of the Harvard-Smithsonian Center for Astrophysics.”
“On Monday, a separate group of astronomers said they had managed to weigh precisely, a set of small planets, and found that their densities and compositions almost exactly matched those of Earth. Courtney Dressing, also of the Harvard-Smithsonian Center for Astrophysics said in a news conference, “I’m going to give you the recipe for a rocky planet. She began, take one cup of magnesium…”
“Reviewing the history of exoplanets, Debra Fischer, a Yale astronomer recalled that the first discovery of a planet orbiting another normal star, a Jupiter-like giant, was 20 years ago. Before that, she said, astronomers worried that “maybe the Star Trek’ picture of the universe was not right — and, there was no life anywhere else. Dr. Fischer called the progress in the last two decades, “incredibly moving,” Mr. Overbye noted. “So far,” he adds, “4,175 potential planets, and 1004 of them have been confirmed as real,” according to Michele Johnson, a spokeswoman for NASA’s Ames Research Center, which operates Kepler.
“Most of them however, including those announced on Tuesday, are light years away, too far for detailed study. We will probably never know more about these planets than we do now,” at least in our lifetime, Mr. Overbye wrote. “We can count as many as we like,” said Sarah Seager of the Massachusetts Institute of Technology (MIT), who was not involved in the new work. She added, “until we can observe the atmospheres and assess their greenhouse gas power, we don’t really know what the weather is like on these worlds, whether there is water, or even life, Still,” she said, “it is heartening to have such a growing list,” of potential inhabitable planets.
“Finding Goldilocks planets closer to home will be the job of the Transiting Exoplanet Survey Satellite, scheduled to be launched in 2017; but, if we want to know what the weather is like on these worlds, whether there is water, or even life, more powerful instruments will be needed,” Mr. Overbye observed.
Dr. Seager, and Julianne Dalcanton of the University of Washington are writing a separate report for a consortium of universities that runs observatories. The goal is to have a pool of dozens of “exo-Earth’s,’ to study, in order to have any chance of seeing signs of life, or understanding terrestrial planets,” Dr. Seager said.
What an exciting discovery. I think if I had any other profession — other than the intelligence community which served in for 33yrs., it would be an astronomer. I am impressed by their insatiable and passionate dedication to finding out if we are not alone — in the universe/s. V/R, RCP