Formation and evolution of the Solar System impact event, the Tunguska event, the Chelyabinsk meteor and the impact feature Meteor Crater in Arizona. The process of accretion, therefore, is not complete, and may still pose a threat to life on Earth. Over the course of the Solar System's evolution, comets were ejected out of the inner Solar System by the gravity of the giant planets, and sent thousands of AU outward to form the Oort cloud, a spherical outer swarm of cometary nuclei at the farthest extent of the Sun's gravitational pull. Eventually, after about 800 million years, the gravitational disruption caused by galactic tides, passing stars
Sun and Moon (Middle-earth) light of the Sun before it was tainted by Melkor when he ravished Arien. The name of Narsil, the sword of King Elendil (later reforged for Aragorn as Andúril), contains the elements "nar" and "thil," "fire" and "white light" respectively in Quenya, referring to the Sun and Moon. The Man in the Moon is even described in those writings, as being an old Elf who secretly hid on the island of the Moon, and built a minaret there. This is alluded to further in Tolkien's "Roverandom", in which the Man in the Moon also lives in a minaret. Combined with