  On 1 February 2011 the Kepler Mission released data for 156,453 stars
observed from the beginning of the science observations on 2 May through 16
September 2009. There are 1235 planetary candidates with transit like
signatures detected in this period. These are associated with 997 host stars.
Distributions of the characteristics of the planetary candidates are separated
into five class-sizes; 68 candidates of approximately Earth-size (radius < 1.25
Earth radii), 288 super-Earth size (1.25 Earth radii < radius < 2 Earth radii),
662 Neptune-size (2 Earth radii < radius < 6 Earth radii), 165 Jupiter-size (6
Earth radii < radius < 15 Earth radii), and 19 up to twice the size of Jupiter
(15 Earth radii < radius < 22 Earth radii). In the temperature range
appropriate for the habitable zone, 54 candidates are found with sizes ranging
from Earth-size to larger than that of Jupiter. Five are less than twice the
size of the Earth. Over 74% of the planetary candidates are smaller than
Neptune. The observed number versus size distribution of planetary candidates
increases to a peak at two to three times Earth-size and then declines
inversely proportional to area of the candidate. Our current best estimates of
the intrinsic frequencies of planetary candidates, after correcting for
geometric and sensitivity biases, are 6% for Earth-size candidates, 7% for
super-Earth size candidates, 17% for Neptune-size candidates, and 4% for
Jupiter-size candidates. Multi-candidate, transiting systems are frequent; 17%
of the host stars have multi-candidate systems, and 33.9% of all the candidates
are part of multi-candidate systems.
