Hat-P-7B is an exoplanet that was discovered in 2008. Just like a lot of the other planets, I’ve spoken about this one is also a hot Jupiter. This planet along with Tres-2b is one of the darkest planets observed; it absorbs less than 97% of the light that hits it. The planet is 40x bigger than Jupiter and completes its orbit every 2.2 Earth days. This means Hat-p-7b has an extremely close proximity to its sun and one side is always facing its star, known as tidally locked. As you can imagine the planet’s temperature varies wildly; the day side is around 2500°C (4600°f).
Scientist kept their eyes on this planet through the Kepler telescope. David Armstrong and his team from the University of Warick, noticed the brightness point of Hat-P-7B changing over time. They came to the conclusion winds, are whipping clouds fast around the planet. The clouds on the cold side evaporate, once they reach the hot side which likely causes major storms to brew. According to Warwick University this was also the first time a gas giant, outside our solar system had its weather pattern discovered.
All of these things make this planet interesting, but something else makes it really stand out. The clouds on Hat-P-7B, are not like the normal clouds we know. We can expect these clouds to look stunning, as they are made out of corundum. In short rubies and sapphires are a variation of corundum. It’s so hot the minerals reach a temperature where they are vaporised, before raining down gemstones on the cold side. This planet might literally rain rubies and sapphires.
Source
https://warwick.ac.uk/newsandevents/news/winds_of_rubies/
https://exoplanets.nasa.gov/news/1397/winds-of-rubies-and-sapphires-strike-the-sky-of-giant-planet/