Back in 2011, astronomers used the Kepler telescope to examine the Kepler 10 star system, with some pretty amazing results. Kepler is designed to search the distant stars for far-off exoplanets by measuring the size of the shadow they cast as they go past their stars, and Kepler 10-c cast a rather large shadow, initially making the scientists to expect to find yet another gas giant simply because of the enormity of the planet.
However, using other equipment to determine the planet’s mass, they realized that Kepler 10-c weighed far too much to be made up of anything lighter than dense rock. That was a huge surprise, as current theory had said the Kepler 10 system had formed less that 3 billion years after the Big Bang explosion. Popular belief up to that point in time said that the primary elements existing during that time were hydrogen and helium. There wasn’t supposed to have been enough rocky material in the universe to build a planet of that size until much later, when the hydrogen and helium atoms started combining to make the greater elements.
Kepler 10-c defies the notion that once any planet got to be about ten times the mass of earth it would have so much gravitational pull that hydrogen atoms would not be able to escape, and it would therefore have to balloon out and become a gas world like Jupiter. In fact, current scientific theories maintain that a planet like Kepler 10-c shouldn’t exist at all.
But exist it does, and it’s quite impressive. This planet is 18,000 miles wide, and it orbits its star every 45 days. It can be found in the constellation of Draco, about 560 light-years from Earth.
Kepler 10-b was formed around the same time, but somehow that exoplanet ended up being much smaller than its nearest neighbor, and its orbit is twice as fast, circling the star every 20 days. Kepler 10-b is also rocky, but volcanic in nature. Because of the added heat, most of its surface is probably covered in molten lava.
This just goes to show that even when they form at the same time, two planets can be vastly different, and even in a star system that should have been devoid of enough rock to make such worlds, nature can find a way.
The understanding of how our universe was formed is quite complex, but the video below might be helpful in shedding a little light on how it was done…