In the search for Earth’s siblings, astronomers often focus on rocky planets, and for good reason: in our Solar System, planets similar to Earth are located only in the habitable zone. But this does not have to be the case in other solar systems. There, gas giants as big as Jupiter or even bigger could be located in the habitable zone of their host star. The habitable zone might even be larger in these systems, because these giant planets could also provide energy to the moons in their orbit. (more…)