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) Sun. In the universe of Middle-earth, the Sun is generally regarded as feminine, in recognition of Arien. This gender corresponds with Sól (Sun), the personified in Germanic mythology. The Maia Tilion was chosen to guide the vessel of the Moon. Names of the Moon amongst the Elves included Isil or "The Sheen", a name given to it by the Vanyar; Ithil, the common name for the Moon in Sindarin, as seen in "Minas Ithil" (later Minas Morgul) and the Gondorian province of Ithilien; and Rána, or "The Wayward", a name given to the Moon by the Noldor. A poetic name