A Distant Blue Star Hosts One of the Most Extreme Exoplanets Known to Science

HD 133112 is a blue A-type star some 322 light years away in Libra… 2,4 times the dimensions of the Sun and 2200 C hotter, it’s substantially brighter than Sol. In close orbit – 1/5 of an AU – is the Jupiter-like planet WASP 189b. The close proximity leads to a daytime surface temperature of 3200C. Which makes one wonder how big that gas giant originally was, and how fast it’s atmosphere is currently blowing away.

There is every possibility that a terrestrial world might orbit out in the habitable zone. But with a Jupiter-class star in close, it might upset the balance of the system. And I wonder what having a planet shedding mass that fast might do to the outer planets; an Earth-like world might have itself a whole lot of excess hydrogen.