  We present scope (Simulated CCD Observations for Photometric
Experimentation), a Python package to create a forward model of telescope
detectors and simulate stellar targets with motion relative to the CCD. The
primary application of this package is the simulation of the Kepler Space
Telescope detector to predict and characterize increased instrumental noise in
the spacecraft's final campaigns of observation. As the fuel powering the
spacecraft's stabilizing thrusters ran out and thruster fires began to sputter
and fail, stellar Point Spread Functions (PSFs) experienced more extreme and
less predictable motion relative to regions of varied sensitivity on the
spacecraft detector, generating more noise in transiting exoplanet light
curves. Using our simulations, we demonstrate that current de-trending
techniques effectively capture and remove systematics caused by sensitivity
variation for spacecraft motion as high as about ten times that typically
experienced by K2. The scope package is open-source and has been generalized to
allow custom detector and stellar target parameters. Future applications
include simulating observations made by the Transiting Exoplanet Survey
Satellite (TESS) and ground based observations with synthetic atmospheric
interference as testbeds for noise-removal techniques.
