We estimate the reddening and distance of the nearest starburst galaxy IC 10 using deep near infrared JHK _ { S } photometry obtained with the Multi-Object InfraRed Camera and Spectrograph ( MOIRCS ) on the Subaru telescope .
We estimate the foreground reddening toward IC 10 using UBV photometry of IC 10 from the Local Group Survey , obtaining E ( B - V ) = 0.52 \pm 0.04 mag .
We derive the total reddening including the internal reddening , E ( B - V ) = 0.98 \pm 0.06 mag , using UBV photometry of early-type stars in IC 10 and comparing JHK _ { S } photometry of red giant branch stars in IC 10 and the SMC .
Using the 2MASS point source catalog of 20 Galactic globular clusters , we derive a relation between the metallicity [ Fe/H ] _ { CG 97 } and the slope of the red giant branch in the K _ { S } - ( J - K _ { S } ) color-magnitude diagram .
The mean metallicity of the red giant branch stars in IC 10 is estimated to be [ Fe/H ] _ { CG 97 } = -1.08 \pm 0.28 .
The magnitude of the tip of the red giant branch ( TRGB ) of IC 10 in the K _ { S } band is measured to be K _ { S,TRGB } = 18.28 \pm 0.01 .
Based on the TRGB method , we estimate the distance modulus of IC 10 to be ( m - M ) _ { 0 } = 24.27 \pm 0.03 { ( random ) } \pm 0.18 { ( systematic ) } , corresponding to the distance of d = 715 \pm 10 \pm 60 kpc .
This confirms that IC 10 is a member of the Local Group .