The perihelion () of any orbit of a celestial body about the Sun is the point where the body comes nearest to the Sun. It is the opposite of aphelion (), which is the point in the orbit where the celestial body is farthest from the Sun. == Etymology == The words perihelion and aphelion were coined by Johannes Kepler to describe the orbital motion of the planets. The words are formed from the prefixes peri- (Greek: περί, near) and apo- (Greek: ἀπό, away from) affixed to the Greek word for the sun, ἥλιος. Perihelion and aphelion are sometimes incorrectly used for the orbits of objects about bodies...

Coordinated Universal Time abbreviated to UTC, is the primary time standard by which the world regulates clocks and time. It is within about 1 second of mean solar time at 0° longitude; it does not observe daylight saving time. For most purposes, UTC is considered interchangeable with Greenwich Mean Time (GMT), but GMT is no longer precisely defined by the scientific community. The first Coordinated Universal Time was informally adopted on 1 January 1960, but the official abbreviation of UTC and the official English name of Coordinated Universal Time (along with the French equivalent), was not...

Greenwich Mean Time (GMT) is the mean solar time at the Royal Observatory in Greenwich, London. GMT was formerly used as the international civil time standard, now superseded in that function by Coordinated Universal Time (UTC). Today GMT is considered equivalent to UTC for UK civil purposes (but this is not formalised) and for navigation is considered equivalent to UT1 (the modern form of mean solar time at 0° longitude); these two meanings can differ by up to 0.9 s. Consequently, the term GMT should not be used for precise purposes. Because of Earth's uneven speed in its elliptical orbit and...

AOE or AoE may refer to: Acute otitis externa, an infection of the external ear canal Alberta Order of Excellence, a high notary award given in Alberta, Canada Anywhere on Earth, a calendar designation Axis of evil, a term used by former U.S. President George W. Bush in his State of the Union address on January 29, 2002 == Culture == Age of Empires, a series of real-time strategy video games, or the first game of the series Area of effect, a term used in gaming to describe area attacks Transformers: Age of Extinction, a 2014 film == Politics == Assembly of Experts == Technology == ATA...