Hubble Identifies Blue Planet with Glass Rain that's Anything but Earth

NASA's ever-peering eye into the heavens, the Hubble Space Telescope, has found a distant planet whose blue hue could be the result of glass rain.

The planet, HD 189733b, is located 63 light-years away, and it wasn't until recently, when the planet passed behind its host star, that scientists were able to surmise that the planet is blue.

"We saw the light becoming less bright in the blue but not in the green or red. Light was missing in the blue but not in the red when it was hidden," said one of the researchers involved in the study, Frederic Pont from University of Exeter in South West England. "This means that the object that disappeared was blue."

Despite resembling Earth's blue aura from a distance, the giant gas planet is anything but our home planet. Searing daily temperatures up to 2,000 degrees Fahrenheit and 4,500 miles per hour make the planet uninhabitable, and scientists theorize that its blue hue comes doesn't come from the ocean like it does on Earth, but from silicate particles (glass) in the atmosphere that scatter blue light.

Planet HD 189733b belongs to a special class of gas giant planets known as "hot Jupiters" because of its proximity to its star. HD 189733b is only 2.9 million miles from its parent star (by comparison, Earth is 93 million miles from the sun, and Mercury, the closest planet in our solar system is 36 million miles from the sun) and its closeness means that the planet is "gravitationally locked," according to NASA. This means that one side of HD 189733b is always facing the star and the other side is always dark.

Scientists are hoping that by further studying HD 189733b they can glean more about the chemical composition of similar planets.

You can read the fully study detailing the findings here.