/**
 * Utility class for astronomical calculations
 */
export declare class Astronomy {
    /**
     * Calculates the Julian day for a given date
     * @param year The year
     * @param month The month (1-12)
     * @param day The day
     * @param hours The hours (0-23)
     * @returns The Julian day
     */
    static julianDay(year: number, month: number, day: number, hours?: number): number;
    /**
     * Calculates the Julian century for a given Julian day
     * @param julianDay The Julian day
     * @returns The Julian century
     */
    static julianCentury(julianDay: number): number;
    /**
     * Calculates the mean solar longitude in degrees
     * @param julianCentury The Julian century
     * @returns The mean solar longitude in degrees
     */
    static meanSolarLongitude(julianCentury: number): number;
    /**
     * Calculates the mean solar anomaly in degrees
     * @param julianCentury The Julian century
     * @returns The mean solar anomaly in degrees
     */
    static meanSolarAnomaly(julianCentury: number): number;
    /**
     * Calculates the equation of the center of the Sun in degrees
     * @param julianCentury The Julian century
     * @param meanAnomaly The mean anomaly in degrees
     * @returns The equation of the center in degrees
     */
    static solarEquationOfCenter(julianCentury: number, meanAnomaly: number): number;
    /**
     * Calculates the apparent solar longitude in degrees
     * @param julianCentury The Julian century
     * @param meanLongitude The mean longitude in degrees
     * @returns The apparent solar longitude in degrees
     */
    static apparentSolarLongitude(julianCentury: number, meanLongitude: number): number;
    /**
     * Calculates the altitude of a celestial body in degrees
     * @param observerLatitude The observer's latitude in degrees
     * @param declination The declination of the celestial body in degrees
     * @param localHourAngle The local hour angle of the celestial body in degrees
     * @returns The altitude of the celestial body in degrees
     */
    static altitudeOfCelestialBody(observerLatitude: number, declination: number, localHourAngle: number): number;
    /**
     * Calculates the days since the winter solstice
     * @param dayOfYear The day of the year (1-366)
     * @param year The year
     * @param latitude The latitude in degrees
     * @returns The number of days since the winter solstice
     */
    static daysSinceSolstice(dayOfYear: number, year: number, latitude: number): number;
    /**
     * Adjusts the morning twilight time based on the season and latitude
     * @param latitude The latitude in degrees
     * @param day The day of the year (1-366)
     * @param year The year
     * @param sunrise The sunrise time
     * @returns The adjusted morning twilight time
     */
    static adjustMorningTwilight(latitude: number, day: number, year: number, sunrise: Date): Date;
    /**
     * Adjusts the evening twilight time based on the season and latitude
     * @param latitude The latitude in degrees
     * @param day The day of the year (1-366)
     * @param year The year
     * @param sunset The sunset time
     * @returns The adjusted evening twilight time
     */
    static adjustEveningTwilight(latitude: number, day: number, year: number, sunset: Date): Date;
}