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import type { EquatorialCoordinate, GeographicCoordinate, HorizontalCoordinate, Interval } from './common';
import { type Planet } from './planets';
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type Target = {
    name: string;
} & HorizontalCoordinate & EquatorialCoordinate;
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export type Conjunction = {
    datetime: Date;
    targets: [Target, Target];
    angularSeparation: number;
    ra: number;
    dec: number;
};
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/**
 *
 * isPlanetaryConjunction()
 *
 * Technically, a conjunction is when two celestial objects have the same right ascension or ecliptic longitude, however
 * in practice, it is when they are close together in the sky. This function tests for the latter.
 *
 * @param datetime - The date and time of the observation to test for conjunction.
 * @param observer - The geographic coordinate of the observer.
 * @param planets - The two planets to test for conjunction.
 * @param horizon - The minimum altitude of the planets above the horizon.
 * @param angularSeparationThreshold - The minimum angular separation of the planets.
 * @returns The conjunction of the two planets if they are in conjunction, otherwise false.
 *
 */
export declare const isPlanetaryConjunction: (datetime: Date, observer: GeographicCoordinate, planets: [Planet, Planet], params?: {
    horizon?: number;
    angularSeparationThreshold?: number;
}) => Conjunction | false;
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/**
 *
 * isConjunction()
 *
 * Tests for a conjunction between two targets, where a conjunction is defined as an angular separation
 * of less than the threshold given, which is by default three degrees.
 *
 * The objects also have to be above the local observer's horizon, which is by default six degrees
 * to ensure good visibility.
 *
 * @param datetime - The date and time of the observation to test for conjunction.
 * @param targets - The two targets to test for conjunction.
 * @param params - The parameters for the conjunction test.
 * @returns The conjunction of the two targets if they are in conjunction, otherwise false.
 *
 */
export declare const isConjunction: (datetime: Date, targets: [Target, Target], params?: {
    horizon?: number;
    angularSeparationThreshold?: number;
}) => Conjunction | false;
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/**
 * findPlanetaryConjunction
 *
 * Finds the next conjunction of two planets within a given time interval.
 *
 * @param startDate - The start date and time of the interval to search for conjunction.
 * @param endDate - The end date and time of the interval to search for conjunction.
 * @param observer - The geographic coordinate of the observer.
 * @param planets - The two planets to test for conjunction.
 * @param horizon - The minimum altitude of the planets above the horizon.
 * @param angularSeparationThreshold - The minimum angular separation of the planets.
 * @param stepMinutes - The step size in minutes for checking conjunction.
 * @returns The conjunction of the two planets if they are in conjunction, otherwise null.
 */
export declare const findPlanetaryConjunction: (interval: Interval, observer: GeographicCoordinate, planets: [Planet, Planet], params?: {
    horizon?: number;
    angularSeparationThreshold?: number;
    stepMinutes?: number;
}) => Conjunction | undefined;
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/**
 *
 * findConjunction()
 *
 * @param interval - The interval to search for the initial conjunction.
 * @param targets - The two targets to test for conjunction.
 * @param params - The parameters for the conjunction test.
 * @returns The conjunction of the two targets if they are in conjunction, otherwise false.
 */
export declare const findConjunction: (interval: Interval, targets: [Target, Target], params?: {
    horizon?: number;
    angularSeparationThreshold?: number;
    stepMinutes?: number;
}) => Conjunction | false;
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/**
 * findPlanetaryConjunctions
 *
 * Finds all conjunctions of the planets within a given time interval, returning only those that are in
 * conjunction with each other (as determined by the angular separation threshold).
 *
 * @param interval - The interval to search for the initial conjunction.
 * @param observer - The geographic coordinate of the observer.
 * @param horizon - The minimum altitude of the planets above the horizon.
 * @param angularSeparationThreshold - The minimum angular separation for conjunction.
 * @param stepMinutes - The step size in minutes for checking conjunction.
 * @returns An array of conjunctions found.
 *
 */
export declare const findPlanetaryConjunctions: (interval: Interval, observer: GeographicCoordinate, params?: {
    horizon?: number;
    angularSeparationThreshold?: number;
    stepMinutes?: number;
}) => Map<string, Conjunction>;
export {};
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