Exoplanet: HD 189733 b

There are so many interesting things to notice about the stellar object in our observable universe. Like for example: there are 4,154 exoplanets discovered till date. Some of these exoplanets carry amazing features to believe even though humans cannot live in it. We came across how the discovery of exoplanets is done, also an exoplanet that rains Iron: Wasp-76b. Not just exoplanets, even the moons and the planets in our own solar system has certain features that amuse us. Here’s another interesting exoplanet named HD 189733 b orbiting its host star HD 189733.

Approximately 64.5 light-years away from our solar system there presents an extrasolar planet “HD 189733 b” in the constellation of Vulpecula. The planet was discovered orbiting its star in the year 2005 by French astronomers. The planet comes under the category of hot Jupiter due to its mass which is 13% larger than Jupiter itself. This makes HD 189733 b as the closest hot Jupiter to Earth as it’s just 64 light-years away. Also, that makes it a prime target for astronomers for this class of exoplanet and its atmosphere around it. The planet orbits in 3 million miles from the star i.e. 30 times closer than Mercury orbits from our Sun. This exoplanet is so close to its star that it takes just 2.2 days to complete its 1 revolution with an orbital speed of 152.5 km/s.

The exoplanet has its temperature 1200 degrees Fahrenheit on the night side and 1700 degrees Fahrenheit on the day side. This planet is tidally locked to its parent star meaning that the planet does not rotate, resulting in permanent day and night. The updated data from the Hubble Space Telescope suggest that the planet looked much like Earth i.e. ‘blue’ in color. Turns out that the blue color may be the result of scattering of light from the parent star due to the silicate particles present in the planet’s atmosphere.

The weather on HD 189733 b will be kind of death-dealing for humans. The winds, composed of silicate particles which blow up to 8700 km/hr. And, since silicates are a component of glass, some researchers have speculated that it actually rains molten glass on the planet.

The observations of HD 189733 b were taken by NASA Chandra Observatory and ESA’s XMM Newton Observatory and they detected the planet’s outer atmosphere is larger than anyone expected it. Sometimes, the star HD 189733 erupts strong solar flares just like our Sun. Apparently, this exoplanet is so close that its outer atmosphere is probably blowing away due to its star. The study estimated that the planet is losing approximately 100 million to 600 million kilograms of mass per second. This produces a comet like tail whenever the planet gets exposed to its star flares.

Another interesting thing about this exoplanet HD 189733 b is that it is called as Earth’s evil twin due to its appearance and its atmospheric conditions. This type of interaction between a star and planet which orbits so close fascinates the astronomers that they suggested that the increased flaring may be due to the interaction of their magnetic field or may be due to its tidal forces.