Kepler Spacecraft
Kepler is a NASA spacecraft equipped with a space observatory designed to discover Earth-like planetsorbiting other stars. The spacecraft is named in honor of German astronomer Johannes Kepler. The spacecraft was launched on March 7, 2009, with a planned mission lifetime of at least 3.5 years.
Kepler's only instrument is a photometer that continuously monitors the brightness of over 145,000[9] main sequence stars in a fixed field of view. This data is analyzed to detect periodic fluctuations that indicate the presence of extrasolar planets (planets outside our solar system) that are in the process of crossing the face of other stars.
'Ball Aerospace & Technologies Corp'. was responsible for developing the Kepler flight system.
On 2 February 2011, the Kepler team announced the results from the data of May to September 2009. They found 1235 planetary candidates circling 997 host stars, more than twice the number of currently known exoplanets. The Kepler results included 68 planetary candidates of Earth-like size and 54 planetary candidates in the habitable zone of their star. The team estimated that 5.4% of stars host Earth-size planet candidates and 17% of all stars have multiple planets. As the mission continues, additional longer period candidates continue to be found - as of September 2011, there were 1781 candidates.
The next data release is scheduled for September 23, 2011, and will consist of one quarter (three months) of data through December 2009.[16] There will be no data released from 2010 or later until June 2012.
The spacecraft has a mass of 1,039 kilograms (2,290 lb), has a 0.95-meter (37.4 in) aperture, and a 1.4-meter (55 in)primary mirror (when it was launched this was the largest on any telescope outside of Earth orbit).[23] The spacecraft has a 115 deg2 (about 12 degree diameter) field of view (FOV), roughly equivalent to the size of one's fist held at arm's length. Of this, 105 deg2 is of science quality, with less than 11% vignetting.
The focal plane of the spacecraft's camera is made up of 42 CCDs at 2200 × 1024 pixels which makes it the largest camera launched into space with a resolution of 95 megapixels.
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