Co-orbital in the context of "Quasi-satellite"

The giant-impact hypothesis, sometimes called the Theia Impact, is an astrogeology hypothesis for the formation of the Moon first proposed in 1946 by Canadian geologist Reginald Daly. The hypothesis suggests that the Proto-Earth collided with a Mars-sized co-orbital protoplanet likely from the L₄ or L₅ Lagrange points of the Earth's orbit approximately 4.5 billion years ago in the early Hadean eon (about 20 to 100 million years after the Solar System formed), and some of the ejected debris from the impact event later re-accreted to form the Moon. The impactor planet is sometimes called Theia, named after the mythical Greek Titan who was the mother of Selene, the goddess of the Moon.

Analysis of lunar rocks published in a 2016 report suggests that the impact might have been a direct hit, causing a fragmentation and thorough mixing of both parent bodies.

Early Earth, also known as Proto-Earth, is loosely defined as Earth in the first one billion years — or gigayear (10 y or Ga) — of its geological history, from its initial formation in the young Solar System at about 4.55 billion years ago (Gya), to the end of the Eoarchean era at approximately 3.5 Gya. On the geologic time scale, this comprises all of the Hadean eon and approximately one-third of the Archean eon, starting with the formation of the Earth about 4.6 Gya, and ended at the start of the Paleoarchean era 3.6 Gya.

This period of Earth's history involved the planet's formation from the solar nebula via a process known as accretion, and transition of the Earth's atmosphere from a hydrogen/helium-predominant primary atmosphere collected from the protoplanetary disk to a reductant secondary atmosphere rich in nitrogen, methane and CO₂. This time period included intense impact events as the young Proto-Earth, a protoplanet of about 0.63 Earth masses, began clearing the neighborhood, including the early Moon-forming collision with Theia — a Mars-sized co-orbital planet likely perturbed from the L₄ Lagrange point — around 0.032 Ga after formation of the Solar System, which resulted in a series of magma oceans and episodes of core formation. After formation of the core, meteorites or comets from the Outer Solar System might have delivered water and other volatile compounds to the Earth's mantle, crust and ancient atmosphere in an intense "late veneer" bombardment. As the Earth's planetary surface eventually cooled and formed a stable but evolving crust during the end-Hadean, most of the water vapor condensed out of the atmosphere and precipitated into a superocean that covered nearly all of the Earth's surface, transforming the initially lava planet Earth of the Hadean into an ocean planet at the early Archean, where the earliest known life forms appeared soon afterwards.

The China National Space Administration (CNSA) is the national space agency of China. Headquartered in Haidian, Beijing, it is responsible for China's civil space programs and international space cooperation. The CNSA is a national bureau under the Ministry of Industry and Information Technology.

Founded in 1993, the CNSA has pioneered a number of achievements in space for China despite its relatively short history, including becoming the first space agency to land on the far side of the Moon with Chang'e 4, bringing material back from the Moon with Chang'e 5 and 6, and being the second agency who successfully landed a rover on Mars with Tianwen-1. Tianwen-2 is en route to explore the co-orbital near-Earth asteroid 469219 Kamoʻoalewa and the active asteroid 311P/PanSTARRS and collecting samples of the regolith of Kamo'oalewa.

514107 Kaʻepaokaʻāwela (/kəˌʔɛpə.oʊkə.ʔɑːˈvɛlə/), provisionally designated 2015 BZ₅₀₉ and nicknamed Bee-Zed, is a small asteroid, approximately 3 km (2 mi) in diameter, in a resonant, co-orbital motion with Jupiter. It is an unusual minor planet in that its orbit is retrograde, which is opposite to the direction of most other bodies in the Solar System. It was discovered on 26 November 2014, by astronomers of the Pan-STARRS survey at Haleakala Observatory on the island of Maui, United States. Kaʻepaokaʻāwela is the first example of an asteroid in a 1:–1 resonance with any of the planets. This type of resonance had only been studied a few years before the object's discovery. One study suggests that it was an interstellar asteroid captured 4.5 billion years ago into an orbit around the Sun.