astronomical measurement
1astronomical unit — (ua or au or AU) a unit of distance used by astronomers to measure distances in the Solar System. One astronomical unit equals the average distance from the center of the Earth to the center of the Sun (mathematically, it is the length of the… …
2Astronomical unit — This article is about unit of length. For the full system of units, see Astronomical system of units. 1 astronomical unit = SI units 149.60×10^6 km 149.60×10^9 m Astronomical units 4.8481 …
3astronomical unit — Astron. a unit of length, equal to the mean distance of the earth from the sun: approximately 93 million miles (150 million km). Abbr.: AU [1900 05] * * * ▪ unit of measurement Comparative data for the Sun, planets, and other solar system… …
4Astronomical seeing — Schematic diagram illustrating how optical wavefronts from a distant star may be perturbed by a layer of turbulent mixing in the atmosphere. The vertical scale of the wavefronts plotted is highly exaggerated. Astronomical seeing refers to the… …
5Measurement — For bust/waist/hip measurement, see BWH. A typical tape measure with both metric and US units and two US pennies for comparison Measurement is the process or the result of determining the ratio of a physical quantity, such as a length, time,… …
6astronomical map — Introduction any cartographic representation of the stars, galaxies, or surfaces of the planets and the Moon. Modern maps of this kind are based on a coordinate system analagous to geographic latitude and longitude. In most cases, modern… …
7Astronomical symbols — This excerpt from the 1833 Nautical Almanac demonstrates the use of astronomical symbols, including symbols for the phases of the moon, the planets, and zodiacal constellations. Astronomical symbols are symbols used to represent various celestial …
8astronomical — adj. (also astronomic) 1 of or relating to astronomy. 2 extremely large; too large to contemplate. Phrases and idioms: astronomical unit a unit of measurement in astronomy equal to the mean distance from the centre of the earth to the centre of… …
9Astronomical time — Time Time, n.; pl. {Times}. [OE. time, AS. t[=i]ma, akin to t[=i]d time, and to Icel. t[=i]mi, Dan. time an hour, Sw. timme. [root]58. See {Tide}, n.] 1. Duration, considered independently of any system of measurement or any employment of terms… …
10Astronomical Unit — noun a unit of length used for distances within the solar system; equal to the mean distance between the Earth and the Sun (approximately 93 million miles or 150 million kilometers) (Freq. 1) • Syn: ↑AU • Hypernyms: ↑astronomy unit * * *… …
