Black as Hell planet

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“The planet orbits the star in a so-called “torch orbit”. One revolution around the star takes only a little less than three Earth days to complete…The temperature of the planet was initially estimated on the basis of 0.3 Bond albedo to be about 1540 K…Its day-side brightness temperature was subsequently directly measured as 2,300 ± 200 K…This is around the boiling point of silicon and well above the melting point of iron.
This planet’s albedo has not been measured directly. The initial estimate of 0.3 had come from averaging Sudarsky’s theoretical classes IV and V. The planet’s extremely high temperature has forced astronomers to abandon that estimate; now, they predict that the planet must absorb essentially all of the starlight that falls on it — that is, effectively zero albedo…Much of the absorption takes place at the top of its atmosphere.
The outer shell of dark, opaque, hot clouds are usually thought to be vanadium and titanium oxides (“pM planets”), but other compounds like tholins cannot be ruled out as yet.
It may have an exceptionally large core composed of elements heavier than hydrogen and helium…the initial theoretical models gave the core a mass of 70 times Earth’s mass; further refinements suggest 80-110 Earth masses. As a result, the planet has been described as a “super-Neptune”, in analogy to the core-dominated outer ice giants of our solar system, though whether the core of HD 149026 b is mainly icy or rocky is not currently known. Robert Naeye in Sky & Telescope claimed “it contains as much or more heavy elements (elements heavier than hydrogen and helium) than all the planets and asteroids in our solar system combined”.”

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