Scientists discover a super-Earth. Something about it is strange.

Scientists found an intriguing world in our galaxy. They confirmed the existence of a rocky planet, called a "super-Earth," that's some six times as massive as Earth. While the world HD 20794 d is larger than our planetary home, it's relatively low-mass compared to the huge and inhospitable Jupiter-like gas giants out there. Importantly, it inhabits a compelling part of its solar system, a region called the habitable or "Goldilocks" zone, where liquid water could exist on a world's surface. (Ear