Planet Hunters: Assessing the Kepler Inventory of Short Period Planets

TL;DR

This study uses citizen science to analyze Kepler data, demonstrating that human classifiers are highly effective at detecting short-period, large-radius exoplanets, supporting the completeness of the Kepler planet catalog for these types.

Contribution

It introduces a large-scale citizen science approach to exoplanet detection and evaluates human detection efficiency compared to Kepler's automated pipeline.

Findings

Humans are 85% efficient at detecting b4 4 Rb0 planets with periods <15 days.

The Kepler catalog of b4 4 Rb0 short-period planets is nearly complete.

Citizen scientists effectively identify large exoplanets in Kepler data.

Abstract

We present the results from a search of data from the first 33.5 days of the Kepler science mission (Quarter 1) for exoplanet transits by the Planet Hunters citizen science project. Planet Hunters enlists members of the general public to visually identify transits in the publicly released Kepler light curves via the World Wide Web. Over 24,000 volunteers reviewed the Kepler Quarter 1 data set. We examine the abundance of \geq 2 R\oplus planets on short period (< 15 days) orbits based on Planet Hunters detections. We present these results along with an analysis of the detection efficiency of human classifiers to identify planetary transits including a comparison to the Kepler inventory of planet candidates. Although performance drops rapidly for smaller radii, \geq 4 R\oplus Planet Hunters \geq 85% efficient at identifying transit signals for planets with periods less than 15 days for the Kepler sample of target stars. Our high efficiency rate for simulated transits along with recovery of the majority of Kepler \geq 4 R\oplus planets suggest suggests the Kepler inventory of \geq 4 R\oplus short period planets is nearly complete.