# The Pointing Limits of Transiting Exoplanet Light Curve Characterization with Pixel Level De-correlation

## TL;DR

This paper introduces a Python tool to simulate CCD detector noise and motion effects on exoplanet transit data, demonstrating current de-trending methods' effectiveness even under extreme spacecraft motion conditions.

## Contribution

The scope package is a versatile, open-source simulation tool that models detector behavior and stellar motion, aiding in the development of noise-removal techniques for space and ground-based observations.

## Key findings

- Current de-trending techniques effectively remove systematics up to ten times typical spacecraft motion.
- The scope package can simulate various detector and stellar parameters for diverse observational scenarios.
- Future work includes applying the tool to TESS data and ground-based atmospheric interference simulations.

## Abstract

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.