A megametre (American spelling: megameter, symbol: Mm) is a unit of length equal to 10⁶ metres (from the Greek words megas = big and metro = count/measure). Its customary equivalent is 621.37 miles. American English or U.S. English is the form of the English language used mostly in the United States of America. ... In physics and metrology, units are standards for measurement of physical quantities that need clear definitions to be useful. ... In general English usage, length (symbols: l, L) is but one particular instance of distance – an objects length is how long the object is – but in the physical sciences and engineering, the word length is in some contexts used synonymously with distance. Height is vertical distance; width (or breadth... The metre, symbol: m, is the basic unit of distance (or of length, in the parlance of the physical sciences) in the International System of Units. ... A mile is any of several units of distance, or, in physics terminology, of length. ...

Megametres are rarely seen in practical use, because they are too big for most terrestrial tasks. They can also be easily confused with millimetres (mm). Still there are a number of "megametre fans". Megametres are also occasionally found in science fiction. A millimetre (American spelling: millimeter, symbol mm) is an SI unit of length that is equal to one thousandth of a metre. ... Science fiction is a form of speculative fiction principally dealing with the impact of imagined science and technology, or both, upon society and persons as individuals. ...

• The Earth's polar circumference is 39.94 Mm +
• The distance from Amsterdam to Bordeaux is approximately 1 Mm +
• The Earth's equatorial diameter is 12.76 Mm +
• The mean distance from the Earth to the Moon is 384.4 Mm +
• Jupiter's equatorial diameter is 143 Mm.

kilometre << megametre << gigametre Earth, also known as the Earth or Terra, is the third planet outward from the Sun. ... The circumference is the distance around a closed curve. ... Amsterdam Location Country The Netherlands Province North Holland Population 739,295 (1 January 2005) Coordinates 4°89E - 52°37N Website www. ... City motto: Lilia sola regunt lunam undas castra leonem. ... Earth, also known as the Earth or Terra, is the third planet outward from the Sun. ... The equator is an imaginary line drawn around a planet, halfway between the poles. ... For the geometric term, see diameter. ... Earth, also known as the Earth or Terra, is the third planet outward from the Sun. ... Crust composition Oxygen 43% Silicon 21% Aluminium 10% Calcium 9% Iron 9% Magnesium 5% Titanium 2% Nickel 0. ... Atmospheric characteristics Atmospheric pressure 70 kPa Hydrogen ~86% Helium ~14% Methane 0. ... The equator is an imaginary line drawn around a planet, halfway between the poles. ... For the geometric term, see diameter. ... A kilometre (American spelling: kilometer, symbol: km) is a unit of length equal to 1000 metres (from the Greek words khilia = thousand and metro = count/measure). ... A gigametre (American spelling: gigameter) (symbol: Gm) is a unit of length equal to 109 metres. ...

See also

• 1 E6 m
• SI
• SI prefix
• Orders of magnitude
• light year
• parsec

A megameter is also a type of astrometrical instrument used for determining longitude by observation of the stars. To help compare different orders of magnitude this page lists lengths between 106 and 107 m (1,000 and 10,000 km). ... The International System of Units (abbreviated SI from the French phrase, Système International dUnités) is the most widely used system of units. ... An SI prefix is a prefix which can be applied to any unit of the International System of Units (SI) to give subdivisions and multiples of that unit. ... An order of magnitude is the class of scale or magnitude of any amount, where each class contains values of a fixed ratio to the class preceding it. ... A light year, abbreviated ly, is the distance light travels in one year: roughly 9. ... The parsec (symbol pc) is a unit of length used in astronomy. ... Astrometry is a part of Astronomy and deals with the positions of stars and other celestial bodies, their distances and movements. ... Map of Earth showing curved lines of longitude Longitude, sometimes denoted λ, describes the location of a place on Earth east or west of a north-south line called the Prime Meridian. ... The Pleiades star cluster A star is any massive gaseous body in outer space, just like the Sun. ...