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We observed GD\,1212 (GJ\,4355, WD\,2336$-$079, catalog no. 60017836, WD\,J233850.74$-$074119.9) for a total of 264.5\,hr using the {\em Kepler} spacecraft in two-wheel mode. With only two working reaction wheels, the spacecraft pointing cannot be
stabilised stabilized in three axes. By pointing the
boresight bore-sight close to the plane of the spacecraft's orbit \citep[within about a degree of the ecliptic,][]{Howell14}, the unconstrained spacecraft roll is placed in equilibrium with respect to the solar pressure, the dominant external force exerted on the spacecraft.
The unconstrained spacecraft roll is an unstable equilibrium, and the pointing needs to be corrected every $3-6$\,hr by firing the thrusters. No data is lost during a thruster firing (known as a reset), but the change in attitude causes a strong jump in the measured flux from the star. The spacecraft rolls by no more than 25 arcsec between resets, which corresponds to motion of a star at the extreme edge of the field of view by no more than 1 pixel. {\em K2} can point a single field for up to 80 days, before the angle of the sun with respect to the solar panels exceeds allowed limits. \citet{Putnam14} provides further details of the capabilities and limitations two wheel operation.
%Resats -- I don't think I need to talk about these
%Each one loses 1 LC and 27 SC.
We collected data on GD\,1212 from 2014\,Jan\,17 to 2014\,Feb\,13 in short-cadence mode (SC), where each exposure is 58.8\,s.
After the first 2.6 days, our observing were interrupted for 15.1\,days by a safe-mode event and subsequent engineering fault analysis. The
entire final 9.0-day light curve
for GD\,1212 can be found in
Figure\,\ref{fig:GD1212lc}, which we use as the basis of our analysis in Section\,\ref{sec:analysis}. Figure\,\ref{fig:GD1212lc}. We have removed all points
which for one reason or another fall falling more than 4$\sigma$ from the light curve mean, resulting in
a duty cycle of 98.8\% for the 2.6- and 9.0-day
observations. Our observing was interrupted for 15.1\,days by observations with a
safe-mode event and subsequent engineering fault analysis, which explains the large gap in the top panel duty cycle of
Figure\,\ref{fig:GD1212lc}. more than 98.2\% and 98.9\%, respectively.
In contrast to the primary mission where only small masks were placed around each star, the data on GD\,1212 were collected using a $50 \times 50$ pixel ``super aperture.'' We expect the aperture size used in two-wheel mode will decrease as confidence in the spacecraft pointing ability increases. The observed pixels were processed through the CAL module of the {\em Kepler} pipeline \citep{Quintana10} to produce target pixel files (TPFs); light curve files were not produced for this commissioning data. TPF data for all stars observed during this engineering run are available at the MAST Kepler archive\footnote{\url{http://archive.stsci.edu/kepler}}.
Our final 9.0-day dataset is nearly continuous
(with a duty cycle of 98.9\%), yielding and has a formal frequency resolution of 1.29 \muhz. The median noise level
in the Fourier transform (FT) near 500 and 1500 \muhz\ for this 9.0-day run is roughly 0.0036\% (36 ppm). For the entire 26.7-day (42.8\% duty cycle) data set, the median noise level is roughly 0.0028\% (28 ppm).
