KID 8561063 - KOI 961 - Kepler-42

Small star with 3 confirmed small planets.

K00961.01, P1=1.2137703 days, R1=0.87 R_Earth,

K00961.02, P2=0.4532875 days, R2=0.92 R_Earth,

K00961.03, P3=1.8651086 days, R3=0.69 R_Earth.

Posted February 17, 2015 3:50 PM

it seems a close companion star caused some light blending.

Do you have a source for that? Because even though the star is magnitude 16, there are no similarly bright stars nearby.

I think what you are alluding to is one of the main issues with observation of such a small star is that its transits are extremely short - this one's are 20 - 30 minutes long, which is similar to the Kepler long-cadence exposure time (29-and-a-bit minutes). This distorts the transit profile by making it more V-shaped, which results in the modelled transit having a higher impact parameter (often over 1), thus making the modelled transiting bodies' radii larger than they actually are to a significant degree. This was exemplified in a recent paper.

Thus, the smaller radii remain correct.

Posted February 17, 2015 9:10 PM

by zoo3hans

@Shellface

You're right, I confused the star with another one in the paper http://arxiv.org/abs/1201.2189 , I have now put in the numbers from http://exoplanetarchive.ipac.caltech.edu/cgi-bin/TblView/nph-tblView?app=ExoTbls&config=cumulative&constraint=koi_pdisposition+like+'CANDIDATE'

Posted February 18, 2015 8:42 AM

KID 8561063 - KOI 961 - Kepler-42 - APH000053n