Future of Earth Sun. The drag from the solar atmosphere may cause the orbit of the Moon to decay. Once the orbit of the Moon closes to a distance of , it will cross the Earth's Roche limit. This means that tidal interaction with the Earth would break apart the Moon, turning it into a ring system. Most of the orbiting ring will then begin to decay, and the debris will impact the Earth. Hence, even if the Earth is not swallowed up by the Sun, the planet may be left moonless. The ablation and vaporization caused by its fall on a decaying
Counter-Earth its planets—at the center of the solar system because of the gravitational pull of the most massive planet—Jupiter. The Sun wobbles around the "true" center known as a barycenter, which lies just inside the Sun. When the Sun's position is 90 degree from the barycenter relative to Earth, it would come close to "unblocking" from view a planet 180 degrees from Earth, enough to reveal the aforementioned hypothetical signature. For a Counter-Earth orbiting the same path as Earth to always stay 180 degrees from Earth, the two planets would have to have circular orbits, but Earth's orbit is elliptical. According