:INFO Terrestrial around KOI-55 It is 0.76 times Earth's radius, closest in size to Venus, and 0.4 times Earth's mass. A year there lasts 5.8 hours, on an orbit 65 times closer to its star than Mercury is to the Sun. Its equilibrium temperature is 7114 K (derived from the star rather than measured), hotter than the surface of many stars. The host star KOI-55 runs at 27730 K with 0.50 times the Sun's mass. :COUNTER 7114 K: hot enough to vaporise rock on the dayside :STATS [icon:TARGET] Radius | 0.76 Earth radii [icon:CHART] Mass | 0.4 Earth masses [icon:FIRE] Equilibrium temperature | 7114 K (derived) [icon:CLOCK] One year | 5.8 hours [icon:BOLT] Orbit radius | 0.0060 AU [icon:STAR] Host star | KOI-55 at 27730 K [icon:USERS] Distance | 4015 light-years :CHECKLIST The state of the record for this planet [ ] A size. Yes. [ ] A weight, not just a width. Yes. [ ] A density, so rock and gas can be told apart. No. [ ] An orbital distance. Yes. [ ] A measured temperature rather than a derived one. No. [ ] An eccentricity, so the orbit shape is known. No. :NOTE The archive lists no measured equilibrium temperature for this planet. The 7114 K quoted here is derived from the star's output and the orbital distance, assuming a third of the light is reflected. It is an estimate from two numbers, not an observation. :NOTE KOI-55 has 2 known planets. Planets in company tug on each other, and those tugs are measurable, which is how masses get pinned down without a wobble. :NOTE Found by Kepler in 2011. Kepler stared at one patch of sky for four years, which is why so many of its planets have short periods: a planet only counts once you have seen it cross several times. :THREAD :LINK https://exoplanetarchive.ipac.caltech.edu/overview/KOI-55%20b NASA Exoplanet Archive: the full record for KOI-55 b