Astronomers announced in an American Astronomical Society meeting that they have discovered a new planet. That’s not new because there are other so-called planets out there. But this gets tricky when you try to define “planet.” We didn’t have a concrete definition for what a planet is until the mid-2000s. But still there is discussion and debate on that issue of definition. Now we’ve discovered mega-Earth i.e., Kepler-10c. Surprise! Since we have believed that most planets that huge were made up of mostly gas, now, according to discovery, we know differently.