The Twelfth PlanetHunters Habitable Zone Candidate

Sharp eyed volunteers at PlanetHunters have identified another set of transits that seem to reveal another exoplanet candidate in the habitable zone of its host star.

One of the transits visible in Quarter 6 PDC_SAP flux

The target is KIC 4947556; a magnitude 13.2 star interpreted in the catalog as a Type K dwarf of 4907(K) and a stellar radius of 0.9 compared to Sol. The public light curve exhibits significant variations throughout the time series, resulting in a group of transits that are not immediately obvious to the eye despite their ~141 day period.

Example of PDC_SAP time series for Quarters 4 and 5

The surrounding field of view is relatively clear and strong offsets are not present in the data correlating to the transit events, however there is a possible secondary source in the form of a very slight 'bulge' that will need to be evaluated for interference along with the usual checks for confusion with a faint eclipsing binary in the background.

Surrounding field sources

Preliminary fitting and characterization work done by PH Talk users Zoo3hans and Kianjin indicate this candidate may exist in the form of a 3.68xRe 'Warm Neptunian' orbiting at 0.52AU with an equilibrium temperature of 278 to 283K. 

                                          PH Talk  Discussion

This candidate follows close on the heels of the potential HZ exoplanets found earlier this month at KIC 9886255 and KIC 4820550.


Further recent Exoplanet reading:

New Mission Manager Update

Do two of the top 6 'Potential Habitable Planets' @ Gliese 581 actually exist?

Extremities of the Exoplanet Density Distribution  

PlanetHunters Blog @ Zooniverse: Sounding Good

The Nine PlanetHunters Habitable Zone Candidates