Scientists have discovered a new planet with the mass of Earth, orbiting its star at the same distance that we orbit our sun. The planet is likely far too cold to be habitable for life as we know it, however, because its star is so faint. But the discovery adds to scientists' understanding of the types of planetary systems that exist beyond our own. Read more
Scientists have discovered a new planet with the mass of Earth, orbiting its star at the same distance that we orbit our sun. The planet is likely far too cold to be habitable for life as we know it, however, because its star is so faint. But the discovery adds to scientists' understanding of the types of planetary systems that exist beyond our own. Read more
Title: The Lowest Mass Ratio Planetary Microlens: OGLE 2016-BLG-1195Lb Author: I.A. Bond, D.P. Bennett, T. Sumi, A. Udalski, D. Suzuki, N.J. Rattenbury, V. Bozza, N. Koshimoto, F. Abe, Y. Asakura, R.K. Barry, A. Bhattacharya, M. Donachie, P. Evans, A. Fukui, Y. Hirao, Y. Itow, M.C.A. Li, C.H. Ling, K. Masuda, Y. Matsubara, Y. Muraki, M. Nagakane, K. Ohnishi, C. Ranc, To. Saito, A. Sharan, D.J. Sullivan, P.J. Tristram, T. Yamada, T. Yamada, A. Yonehara, J. Skowron, M.K. Szymanski, R. Poleski, P. Mroz, I. Soszynski, P. Pietrukowicz, S. Kozlowski, K. Ulaczyk, M. Pawlak
We report discovery of the lowest mass ratio exoplanet to be found by the microlensing method in the light curve of the event OGLE~2016--BLG--1195. This planet revealed itself as a small deviation from a microlensing single lens profile from an examination of the survey data soon after the planetary signal. The duration of the planetary signal is ~2.5hours. The measured ratio of the planet mass to its host star is q=4.2±0.7 x 10^-5. We further estimate that the lens system is likely to comprise a cold ~3 Earth mass planet in a ~2 AU wide orbit around a 0.2 Solar mass star at an overall distance of 7.1 kpc.
Title: An Earth-mass Planet in a 1-AU Orbit around a Brown Dwarf Author: Y. Shvartzvald, J. C. Yee, S. Calchi Novati, A. Gould, C.-U. Lee, C. Beichman, G. Bryden, S. Carey, B. S. Gaudi, C. B. Henderson, W. Zhu, M. D. Albrow, S.-M. Cha, S.-J. Chung, C. Han, K.-H. Hwang, Y. K. Jung, D.-J. Kim, H.-W. Kim, S.-L. Kim, Y. Lee, B.-G. Park, R. W. Pogge, Y.-H. Ryu, I.-G. Shin
We combine Spitzer and ground-based KMTNet microlensing observations to identify and precisely measure an Earth-mass (1.32^{+0.41}_{-0.28} earth mass) planet OGLE-2016-BLG-1195Lb at 1.11^{+0.13}_{-0.10} AU orbiting a 0.072^{+0.014}_{-0.010} solar mass ultracool dwarf, likely a brown dwarf. This is the lowest-mass microlensing planet to date. At 4.20^{+0.29}_{-0.34} kpc, it is the third consecutive case among the Spitzer "Galactic distribution" planets toward the Galactic bulge that lies in the Galactic disk as opposed to the bulge itself, hinting at a skewed distribution of planets. Together with previous microlensing discoveries, the seven Earth-size planets orbiting the ultracool dwarf TRAPPIST-1, and the detection of disks around young brown dwarfs, OGLE-2016-BLG-1195Lb suggests that such planets might be common around ultracool dwarfs. It therefore sheds light on the formation of both brown dwarfs and planetary systems at the limit of low-mass protoplanetary disks.