Scientists Determine Color of Planet Orbiting Another Star for First Time

It's blue


For the first time, astronomers have determined the true colour of a planet orbiting another star.

The world, known as HD189733b, has a deep azure hue—probably the result of silicate (glass) rain in the atmosphere, which scatters blue light.

Details of the discovery, made with the Hubble Space Telescope, are to appear in Astrophysical Journal Letters.

Although it might resemble Earth from a distance, HD189733b is a huge gas giant which orbits close to its host star.