Kepler K2 Precision Lightcurve Observations of Pluto: Preliminary Results
Abstract
Pluto is a key object in the third zone of our Solar System and provides important insight into formation and collisional processes that were at work in the early solar system. In July 2015 the New Horizons spacecraft successfully obtained high resolution fly-by clear filter imaging observations of the Pluto system. We report on our continued monitoring of the Pluto system from October-December 2015 using the Kepler spacecraft's imaging photometer during Campaign 7 of the K2 extended mission (Howell et al. 2014). We obtained an unprecedented 83-day nearly continuous lightcurve with measurements every 30 minutes using Kepler's long cadence sampling. The result was 3,980 discrete, unresolved measurements of the combined Pluto system. The 3-month baseline allowed us to sample rotational variations and solar phase angles ranging from 1.1°-1.7° during the period of observation. This dataset is a key baseline for advancing the study of Pluto's actively evolving surface-atmosphere interaction as revealed by the surface geomorphology discovered by New Horizons. Our challenge is to gain an understanding of the ways in which Pluto's surface can be evolving as it recedes from the Sun, and of the influence of Pluto and Charon on each other. In this paper, we present our preliminary results from our K2 dataset. We describe the challenges in reducing the K2 lightcurve data for a target moving across the K2 FOV, and our progress in understanding the lightcurve's variability, which in our current reduction is due to a combination of systematics in the K2 dataset and inherent characteristics of the Pluto system's rotation and changing orbital geometry wrt the Sun and the Earth.This work was supported by NASA's K2 and New Horizons missions.
- Publication:
-
AAS/Division for Planetary Sciences Meeting Abstracts #48
- Pub Date:
- October 2016
- Bibcode:
- 2016DPS....4821301L