@observerly/astrometry
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observerly's lightweight, zero-dependency, type safe astrometry library written in Typescript for calculating the position of celestial objects in the sky.
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TypeScript
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/**
*
* The approximateed average radius of the Earth in meters.
*
*/
export declare const EARTH_RADIUS: 6378137.8;
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/**
*
* The Astronomical Unit (AU) is a unit of length defined as the average distance
* between the Earth and the Sun.
*
*/
export declare const AU_IN_METERS: 149597870700;
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export declare const SECONDS_IN_HOUR = 3600;
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export declare const SECONDS_IN_DAY = 86400;
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export declare const SECONDS_IN_YEAR = 31556925.445;
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/**
*
* The speed of light in a vacuum is a fundamental physical constant that is
* the speed at which light propagates in a vacuum.
*
* The speed of light in a vacuum is exactly 299,792,458 meters per second.
*
*/
export declare const SPEED_OF_LIGHT = 299792458;
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export declare const c = 299792458;
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/**
*
* The previous standard epoch "J1900" was defined by international agreement to
* be equivalent to: The Gregorian date January 0.5, 1900, at 12:00 TT (Terrestrial Time),
* equivalent to noon on December 31, 1899.
*
* The Julian date 2415020.0 TT (Terrestrial Time).
*
*/
export declare const J1900: 2415020;
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/**
*
* The standard epoch "J1970" is defined by international agreement to be equivalent
* to: The Gregorian date January 1, 1970, at 00:00 TT (Terrestrial Time).
*
* The Julian date 2440587.5 TT (Terrestrial Time).
*
* This is useful because it is the "epoch" referenced to the Unix 0 time system. The
* Unix time 0 is exactly midnight UTC on 1 January 1970, with Unix time incrementing
* by 1 for every non-leap second after this.
*
*/
export declare const J1970: 2440587.5;
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/**
*
* The currently-used standard epoch "J2000" is defined by international agreement to
* be equivalent to: The Gregorian date January 1, 2000, at 12:00 TT (Terrestrial Time).
*
* The Julian date 2451545.0 TT (Terrestrial Time).
*
*/
export declare const J2000: 2451545;
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