@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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import type { EclipticCoordinate, EquatorialCoordinate } from './common';
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export declare const SOLAR_TROPICAL_YEAR: 365.242189;
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/**
*
* getSolarMeanAnomaly()
*
* The Sun's mean anomaly is the angle between perigee and the Sun's current position.
*
* @param date - The date to calculate the Sun's mean anomaly for.
* @returns The Sun's mean anomaly at the given date.
*
*/
export declare const getSolarMeanAnomaly: (datetime: Date) => number;
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/**
*
* getSolarEquationOfCenter()
*
* The equation of center is the difference between the mean geometric longitude
* and the mean anomaly.
*
* @param date - The date to calculate the Sun's equation of center for.
* @returns The Sun's equation of center at the given date.
*/
export declare const getSolarEquationOfCenter: (datetime: Date) => number;
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/**
*
* getSolarMeanGeometricLongitude()
*
* The mean geometric longitude for the Sun is the angle between the perihelion
* and the current position of the Sun, as seen from the centre of the Earth.
*
* @param date - The date to calculate the Sun's true geometric longitude for.
* @returns The Sun's true geometric longitude at the given date.
*
*/
export declare const getSolarMeanGeometricLongitude: (datetime: Date) => number;
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/**
*
* getSolarTrueAnomaly()
*
* The true anomaly for the Sun is the angle between the perihelion and the
* current position of the Sun, as seen from the centre of the Earth, corrected
* for the equation of center.
*
* @param date - The date to calculate the Sun's true anomaly for.
* @returns The Sun's true anomaly at the given date.
*
*/
export declare const getSolarTrueAnomaly: (datetime: Date) => number;
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/**
*
* getSolarTrueGeometricLongitude()
*
* The true geometric longitude for the Sun is the angle between the perihelion
* and the current position of the Sun, as seen from the centre of the Earth,
* corrected for the equation of center.
*
* @param date - The date to calculate the Sun's true geometric longitude for.
* @returns The Sun's true geometric longitude at the given date.
*
*/
export declare const getSolarTrueGeometricLongitude: (datetime: Date) => number;
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/**
*
* getSolarEclipticLongitude()
*
* The ecliptic longitude for the Sun is the angle between the perihelion and
* the current position of the Sun, as seen from the centre of the Earth,
* corrected for the equation of center and the Sun's ecliptic longitude at
* perigee at the epoch.
*
* @param date - The date to calculate the Sun's ecliptic longitude for.
* @returns The Sun's ecliptic longitude at the given date.
*
*/
export declare const getSolarEclipticLongitude: (datetime: Date) => number;
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/**
*
* getSolarEclipticCoordinate()
*
* The ecliptic coordinates of the Sun are the Sun's position in the sky as seen
* from the centre of the Earth, corrected for the equation of center and the Sun's
* ecliptic longitude at perigee at the epoch.
*
* @param datetime - The date to calculate the Sun's ecliptic coordinates for.
* @returns The Sun's ecliptic coordinates at the given date.
*/
export declare function getSolarEclipticCoordinate(datetime: Date): EclipticCoordinate & {
R: number;
};
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/**
*
* getSolarEquatorialCoordinate()
*
* The equatorial coordinate of the Sun is the standard equatorial coordinate
* of the Sun, as seen from the centre of the Earth, corrected for the equation
* of center and the Sun's ecliptic longitude at perigee at the epoch.
*
* @param date - The date to calculate the Sun's equatorial coordinate for.
* @returns The Sun's equatorial coordinate at the given date.
*
*/
export declare const getSolarEquatorialCoordinate: (datetime: Date) => EquatorialCoordinate;
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/**
*
* getSolarAngularDiameter()
*
* The Sun's angular diameter is the distance between the Sun's centre and the Sun's limb.
*
* @param date - The date to calculate the Sun's angular diameter for.
* @returns The Sun's angular diameter in degrees
*
*/
export declare const getSolarAngularDiameter: (datetime: Date) => number;
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/**
*
* getSolarDistance()
*
* @param datetime - The date to calculate the distance to the Sun for.
* @returns The distance to the Sun in metres forthe given date.
*/
export declare const getSolarDistance: (datetime: Date) => number;
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export declare const getHeliocentricJulianDate: (datetime: Date) => number;
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