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The prime Kepler mission revealed that small planets (<4 R_earth) are common,especially around low-mass M dwarfs. K2, the re-purposed Kepler mission,continues this exploration of small planets around small stars. Here we combineK2 photometry with spectroscopy, adaptive optics imaging, and archival surveyimages to analyze two small planets orbiting the nearby, field age, M dwarfsK2-26 (EPIC 202083828) and K2-9. K2-26 is an M1.0 +/- 0.5 dwarf at 93 +/- 7 pcfrom K2 Campaign 0. We validate its 14.5665 d period planet and estimate aradius of 2.67^+0.46_-0.42 R_earth. K2-9 is an M2.5 +/- 0.5 dwarf at 110 +/- 12pc from K2 Campaign 1. K2-9b was first identified by Montet et al. 2015; herewe present spectra and adaptive optics imaging of the host star andindependently validate and characterize the planet. Our analyses indicate K2-9bis a 2.25^+0.53_-0.96 R_earth planet with a 18.4498 d period. K2-26b exhibits atransit duration that is too long to be consistent with a circular orbit giventhe measured stellar radius. Thus, the long transits are likely due to thephotoeccentric effect and our transit fits hint at an eccentric orbit. Bothplanets receive low incident flux from their host stars and have estimatedequilibrium temperatures <500 K. K2-9b may receive approximately Earth-likeinsolation. However, its host star exhibits strong GALEX UV emission whichcould affect any atmosphere it harbors. K2-26b and K2-9b are representatives ofa poorly studied class of small planets with cool temperatures that have radiiintermediate to Earth and Neptune. Future study of these systems can providekey insight into trends in bulk composition and atmospheric properties at thetransition from silicate dominated to volatile rich bodies.

Two Small Temperate Planets Transiting Nearby M Dwarfs in K2 Campaigns 0 and 1