A Blue Exoplanet Where It Rains Molten Glass Sideways
Sixty-three light-years away, a deep-blue gas giant scatters glass through its skies on winds seven times the speed of sound.
From a distance, HD 189733b looks reassuringly familiar: a deep cobalt blue, much like Earth seen from orbit. The resemblance ends there. In 2013, the NASA/ESA Hubble Space Telescope measured the true colour of this planet, the first time astronomers had pinned down the visible hue of any world beyond our solar system.
The blue is no ocean. It comes from a hazy, blow-torched atmosphere laced with silicate particles that scatter blue light. At temperatures topping 1,000 °C, those silicates condense into tiny grains of glass.
On this world, getting caught in the rain means death by a thousand cuts.
The planet is a “hot Jupiter,” orbiting its star so closely that its skies are torn by winds reaching 7,000 km/h (about 5,400 mph) — roughly seven times the speed of sound. The result is a place where glass clouds rain sideways, blasted around the globe in a scalding spiral. Lying 63 light-years from Earth in the constellation Vulpecula, HD 189733b remains one of the most studied, and most hostile, exoplanets known.
Sources & references
2 referencesWell-established. Corroborated by 2 independent sources.
