KMTNet & OGLE I-band photometry of KMT-2019-BLG-0842

The Bayesian estimates for the host mass, planet mass, system distance, and planet-host projected separation are M_host_=0.76{+/-}0.40M{sun}, M_planet_=10.3{+/-}5.5M{Earth}, D_L_=3.3{+/-}1.3kpc, and a{perp}=3.3{+/-}1.4 au, respectively.

The consistency of the color and brightness expected from the estimated lens mass and distance with those of the blend suggests the possibility that the most blended light comes from the planet host, and this hypothesis can be established if high-resolution images are taken during the next (2020) bulge season. We discuss the importance of conducting optimized photometry and aggressive follow-up observations for moderately or very high magnification events to maximize the detection rate of planets with very low mass ratios.