  We report on the discovery of three transiting planets around GJ~9827. The
planets have radii of 1.75$_{-0.12}^{+0.11 }$, 1.36$_{- 0.09 }^{+ 0.09}$, and
2.10$_{- 0.15 }^{+ 0.15 }$~R$_{\oplus}$, and periods of 1.20896, 3.6480, and
6.2014 days, respectively. The detection was made in Campaign 12 observations
as part of our K2 survey of nearby stars. GJ~9827 is a $V = 10.39$~mag K6V star
at distance of 30.3 parsecs and the nearest star to be found hosting planets by
Kepler and K2. The radial velocity follow-up, high resolution imaging, and
detection of multiple transiting objects near commensurability drastically
reduce the false positive probability. The orbital periods of GJ~9827~b, c and
d planets are very close to the 1:3:5 mean motion resonance. Our preliminary
analysis shows that GJ~9827 planets are excellent candidates for atmospheric
observations. Besides, the planetary radii span both sides of the rocky and
gaseous divide, hence the system will be an asset in expanding our
understanding of the threshold.
