4. HD 40307g “Super-Earth” HD 40307g orbits comfortably inside the habitable zone of its parent star. It lies about 42 light-years away from Earth in the constellation Pictor. It is so close by that future telescopes may be able to peer at its surface. It orbits its parent star about 56 million miles (90 million kilometers) away, which is just over half of the Earth-sun distance of 93 million miles (150 million kilometers.)