Deep Blue Alien World that Rains Glass is Nothing Like Planet Earth

About 63 light-years away from Earth, a deep, blue planet orbits its own star. Now, astronomers have used NASA's Hubble Space Telescope to learn a little bit more about this cobalt, alien planet. They've discovered exactly where this blue color originates from, revealing that despite its color it's nothing at all like our own blue planet.

The planet was first discovered in 2005, but it wasn't until recently that scientists made further discoveries about its atmosphere. Called HD 189733b, the planet is tidally locked with its parent star, which means that one of its sides is always light and one is always dark. Located only 2.9 million miles from its sun, the blue world can reach extreme temperatures.

Earth appears blue from space due to the reflection of its water. The ocean absorbs red and green wavelengths more strongly than blue light and the shorter blue wavelengths in Earth's sky are selectively scattered by atmospheric oxygen and nitrogen molecules in a process known as Rayleigh scattering. Yet this new planet is blue for an entirely different reason. The turbulent alien world is characterized by a hazy, blow-torched atmosphere with high clouds that are possibly laced with silicate particles. The condensation temperature of silicates could potentially form very small drops of glass that scatter blue light more than red light, giving the planet its blue hue.

"We obviously don't know much on the physics and climatology of silicate clouds, so we are exploring a new domain in atmospheric physics," said Frederic Pont, one of the team members of the new study, in a news release.

The planet's atmosphere is far hotter than Earth's, blazing at a scorching 2,000 degrees Fahrenheit. Superheated winds blast over the surface, howling at 4,500 mph. It's also possible that this world also rains glass, blowing shards sideways under these extreme conditions.

Speculation aside, though, the researchers caution that it's difficult to know exactly what causes the color of a planet's atmosphere. For example, Jupiter is reddish due to unknown color-carrying molecules and Venus does not reflect ultraviolet light due to an unknown UV absorber in the atmosphere. Even so, the new study does reveal a scattering of light, which could mean that this star-scorched world could possess a strange and unique atmosphere including silicate clouds.

The findings will be published in the journal Astrophysical Journal Letters.