But to be fair no one knows if this technique will really work to find Earth-like planets in habitable zone
and no one will know how often they exist until this experiment is complete.
The currently envisioned path forward, as I understand it, is for Kepler to locate earth-sized planets, or at least candidates. At the very least, candidates could be studied by Hubble, Keck, Spitzer, etc to confirm the observations.
NASA to Unveil Kepler Space Telescope Discoveries
Kepler's high sensitivity to both small and large planets enabled the discovery of the exoplanets, named Kepler 4b, 5b, 6b, 7b and 8b......They have orbits ranging from 3.3 to 4.9 days. Estimated temperatures of the planets range from 2,200 to 3,000 degrees Fahrenheit, hotter than molten lava and much too hot for life as we know it......"We expected Jupiter-size planets in short orbits to be the first planets Kepler could detect. It's only a matter of time before more Kepler observations lead to smaller planets with longer period orbits, coming closer and closer to the discovery of the first Earth analog."......Kepler's science instrument, or photometer, already has measured hundreds of possible planet signatures that are being analyzed.
Lots of earth-size planets have been found by Kepler:http://www.ted.com/talks/view/id/920http://nasawatch.com/archives/2010/07/kepler-results.html#more
Quote from: yg1968 on 07/26/2010 03:18 amLots of earth-size planets have been found by Kepler:http://www.ted.com/talks/view/id/920http://nasawatch.com/archives/2010/07/kepler-results.html#moreCANDIDATES! Not earth-size planets confirmed:http://www.space.com/scienceastronomy/kepler-earth-like-exoplanets-100722.html
Characteristics of Kepler planetary candidates based on the first data set: the majority are found to be Neptune-size and smaller Abstract. In the spring of 2009, the Kepler Mission commenced high-precision photometry on nearly 156,000 stars to determine the frequency and characteristics of small exoplanets, conduct a guest observer program, and obtain asteroseismic data on a wide variety of stars. On 15 June 2010 the Kepler Mission released data from the first quarter of observations. At the time of this publication, 706 stars from this first data set have exoplanet candidates with sizes from as small as that of the Earth to larger than that of Jupiter. Here we give the identity and characteristics of 306 released stars with planetary candidates. Data for the remaining 400 stars with planetary candidates will be released in February 2011. Over half the candidates on the released list have radii less than half that of Jupiter. The released stars include five possible multi-planet systems. One of these has two Neptune-size (2.3 and 2.5 Earth-radius) candidates with near-resonant periods.
Two weeks ago, I gave a talk at TED Global 2010 which was very well received, but caused confusion. I talked about Earth-like planets, which many people would equate to Earth-size and "habitable."Earth-size and Earth-like is certainly not the same. Take the example of Venus, an Earth-size planet whose surface will melt lead. I understand that the term "Earth-like" was misleading to most of the media coverage. The Kepler mission is designed to discover Earth-size planets but it has not yet discovered any; at this time we have found only planet candidates.The June 2010 Kepler data release with 306 candidates is an encouraging first step along the road to Kepler's ultimate goals, and specifically - the goal to determine the frequency of Earth-size planets in and near the habitable zone. However, these are candidates, not systems that have been verified sufficiently to be considered true planets. It will take more years of hard work to get to our goal, but we can do it.