// lib/spa.js "use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.spa_calculate = exports.topocentric_azimuth_angle = exports.topocentric_azimuth_angle_astro = exports.topocentric_zenith_angle = exports.topocentric_elevation_angle_corrected = exports.atmospheric_refraction_correction = exports.topocentric_elevation_angle = exports.topocentric_local_hour_angle = exports.topocentric_right_ascension = exports.right_ascension_parallax_and_topocentric_dec = exports.observer_hour_angle = exports.geocentric_declination = exports.geocentric_right_ascension = exports.third_order_polynomial = exports.limit_degrees = exports.rad2deg = exports.deg2rad = exports.SpaData = exports.SPA_ALL = exports.SPA_ZA_RTS = exports.SPA_ZA_INC = exports.SPA_ZA = exports.OutCode = void 0; var OutCode; (function (OutCode) { OutCode[OutCode["SPA_ZA"] = 0] = "SPA_ZA"; OutCode[OutCode["SPA_ZA_INC"] = 1] = "SPA_ZA_INC"; OutCode[OutCode["SPA_ZA_RTS"] = 2] = "SPA_ZA_RTS"; OutCode[OutCode["SPA_ALL"] = 3] = "SPA_ALL"; //calculate all SPA output values })(OutCode = exports.OutCode || (exports.OutCode = {})); //For external reference as per original C definition exports.SPA_ZA = OutCode.SPA_ZA; exports.SPA_ZA_INC = OutCode.SPA_ZA_INC; exports.SPA_ZA_RTS = OutCode.SPA_ZA_RTS; exports.SPA_ALL = OutCode.SPA_ALL; var PI = Math.PI; var SUN_RADIUS = 0.26667; var L_COUNT = 6; var B_COUNT = 2; var R_COUNT = 5; var Y_COUNT = 63; var TermsA; (function (TermsA) { TermsA[TermsA["TERM_A"] = 0] = "TERM_A"; TermsA[TermsA["TERM_B"] = 1] = "TERM_B"; TermsA[TermsA["TERM_C"] = 2] = "TERM_C"; TermsA[TermsA["TERM_COUNT"] = 3] = "TERM_COUNT"; })(TermsA || (TermsA = {})); var TermsX; (function (TermsX) { TermsX[TermsX["TERM_X0"] = 0] = "TERM_X0"; TermsX[TermsX["TERM_X1"] = 1] = "TERM_X1"; TermsX[TermsX["TERM_X2"] = 2] = "TERM_X2"; TermsX[TermsX["TERM_X3"] = 3] = "TERM_X3"; TermsX[TermsX["TERM_X4"] = 4] = "TERM_X4"; TermsX[TermsX["TERM_X_COUNT"] = 5] = "TERM_X_COUNT"; })(TermsX || (TermsX = {})); var TermsPE; (function (TermsPE) { TermsPE[TermsPE["TERM_PSI_A"] = 0] = "TERM_PSI_A"; TermsPE[TermsPE["TERM_PSI_B"] = 1] = "TERM_PSI_B"; TermsPE[TermsPE["TERM_EPS_C"] = 2] = "TERM_EPS_C"; TermsPE[TermsPE["TERM_EPS_D"] = 3] = "TERM_EPS_D"; TermsPE[TermsPE["TERM_PE_COUNT"] = 4] = "TERM_PE_COUNT"; })(TermsPE || (TermsPE = {})); var JDSign; (function (JDSign) { JDSign[JDSign["JD_MINUS"] = 0] = "JD_MINUS"; JDSign[JDSign["JD_ZERO"] = 1] = "JD_ZERO"; JDSign[JDSign["JD_PLUS"] = 2] = "JD_PLUS"; JDSign[JDSign["JD_COUNT"] = 3] = "JD_COUNT"; })(JDSign || (JDSign = {})); var SunState; (function (SunState) { SunState[SunState["SUN_TRANSIT"] = 0] = "SUN_TRANSIT"; SunState[SunState["SUN_RISE"] = 1] = "SUN_RISE"; SunState[SunState["SUN_SET"] = 2] = "SUN_SET"; SunState[SunState["SUN_COUNT"] = 3] = "SUN_COUNT"; })(SunState || (SunState = {})); var TERM_Y_COUNT = TermsX.TERM_X_COUNT; var l_subcount = [64, 34, 20, 7, 3, 1]; var b_subcount = [5, 2]; var r_subcount = [40, 10, 6, 2, 1]; var SpaData = /** @class */ (function () { function SpaData() { //--------------------------Input Valuse this.year = 0; // 4-digit year, valid range: -2000 to 6000, error code: 1 this.month = 0; // 2-digit month, valid range: 1 to 12, error code: 2 this.day = 0; // 2-digit day, valid range: 1 to 31, error code: 3 this.hour = 0; // Observer local hour, valid range: 0 to 24, error code: 4 this.minute = 0; // Observer local minute, valid range: 0 to 59, error code: 5 this.second = 0.0; // Observer local second, valid range: 0 to <60, error code: 6 this.delta_ut1 = 0.0; // Fractional second difference between UTC and UT which is used // to adjust UTC for earth's irregular rotation rate and is derived // from observation only and is reported in this bulletin: // http://maia.usno.navy.mil/ser7/ser7.dat, // where delta_ut1 = DUT1 // valid range: -1 to 1 second (exclusive), error code 17 this.delta_t = 0.0; // Difference between earth rotation time and terrestrial time // It is derived from observation only and is reported in this // bulletin: http://maia.usno.navy.mil/ser7/ser7.dat, // where delta_t = 32.184 + (TAI-UTC) - DUT1 // valid range: -8000 to 8000 seconds, error code: 7 this.timezone = 0.0; // Observer time zone (negative west of Greenwich) // valid range: -18 to 18 hours, error code: 8 this.longitude = 0.0; // Observer longitude (negative west of Greenwich) // valid range: -180 to 180 degrees, error code: 9 this.latitude = 0.0; // Observer latitude (negative south of equator) // valid range: -90 to 90 degrees, error code: 10 this.elevation = 0.0; // Observer elevation [meters] // valid range: -6500000 or higher meters, error code: 11 this.pressure = 0.0; // Annual average local pressure [millibars] // valid range: 0 to 5000 millibars, error code: 12 this.temperature = 0.0; // Annual average local temperature [degrees Celsius] // valid range: -273 to 6000 degrees Celsius, error code 13 this.slope = 0.0; // Surface slope (measured from the horizontal plane) // valid range: -360 to 360 degrees, error code: 14 this.azm_rotation = 0.0; // Surface azimuth rotation (measured from south to projection of // surface normal on horizontal plane, negative east) // valid range: -360 to 360 degrees, error code: 15 this.atmos_refract = 0.0; // Atmospheric refraction at sunrise and sunset (0.5667 deg is typical) // valid range: -5 to 5 degrees, error code: 16 this.function = 0; // Switch to choose functions for desired output (from enumeration) //-----------------ermediate OUTPUT VALUES-------------------- this.jd = 0.0; //Julian day this.jc = 0.0; //Julian century this.jde = 0.0; //Julian ephemeris day this.jce = 0.0; //Julian ephemeris century this.jme = 0.0; //Julian ephemeris millennium this.l = 0.0; //earth heliocentric longitude [degrees] this.b = 0.0; //earth heliocentric latitude [degrees] this.r = 0.0; //earth radius vector [Astronomical Units, AU] this.theta = 0.0; //geocentric longitude [degrees] this.beta = 0.0; //geocentric latitude [degrees] this.x0 = 0.0; //mean elongation (moon-sun) [degrees] this.x1 = 0.0; //mean anomaly (sun) [degrees] this.x2 = 0.0; //mean anomaly (moon) [degrees] this.x3 = 0.0; //argument latitude (moon) [degrees] this.x4 = 0.0; //ascending longitude (moon) [degrees] this.del_psi = 0.0; //nutation longitude [degrees] this.del_epsilon = 0.0; //nutation obliquity [degrees] this.epsilon0 = 0.0; //ecliptic mean obliquity [arc seconds] this.epsilon = 0.0; //ecliptic true obliquity [degrees] this.del_tau = 0.0; //aberration correction [degrees] this.lamda = 0.0; //apparent sun longitude [degrees] this.nu0 = 0.0; //Greenwich mean sidereal time [degrees] this.nu = 0.0; //Greenwich sidereal time [degrees] this.alpha = 0.0; //geocentric sun right ascension [degrees] this.delta = 0.0; //geocentric sun declination [degrees] this.h = 0.0; //observer hour angle [degrees] this.xi = 0.0; //sun equatorial horizontal parallax [degrees] this.del_alpha = 0.0; //sun right ascension parallax [degrees] this.delta_prime = 0.0; //topocentric sun declination [degrees] this.alpha_prime = 0.0; //topocentric sun right ascension [degrees] this.h_prime = 0.0; //topocentric local hour angle [degrees] this.e0 = 0.0; //topocentric elevation angle (uncorrected) [degrees] this.del_e = 0.0; //atmospheric refraction correction [degrees] this.e = 0.0; //topocentric elevation angle (corrected) [degrees] this.eot = 0.0; //equation of time [minutes] this.srha = 0.0; //sunrise hour angle [degrees] this.ssha = 0.0; //sunset hour angle [degrees] this.sta = 0.0; //sun transit altitude [degrees] //---------------------Final OUTPUT VALUES------------------------ this.zenith = 0.0; //topocentric zenith angle [degrees] this.azimuth_astro = 0.0; //topocentric azimuth angle (westward from south) [for astronomers] this.azimuth = 0.0; //topocentric azimuth angle (eastward from north) [for navigators and solar radiation] this.incidence = 0.0; //surface incidence angle [degrees] this.suntransit = 0.0; //local sun transit time (or solar noon) [fractional hour] this.sunrise = 0.0; //local sunrise time (+/- 30 seconds) [fractional hour] this.sunset = 0.0; //local sunset time (+/- 30 seconds) [fractional hour] } return SpaData; }()); exports.SpaData = SpaData; var copySPA = function (src) { return Array.isArray(src) ? src.map(function (i) { return copySPA(i); }) : typeof src === 'object' ? Object.getOwnPropertyNames(src).reduce(function (o, prop) { Object.defineProperty(o, prop, Object.getOwnPropertyDescriptor(src, prop)); o[prop] = copySPA(src[prop]); return o; }, Object.create(Object.getPrototypeOf(src))) : src; }; //===================Earth Periodic Terms=================== var L_TERMS = [ [ [175347046.0, 0, 0], [3341656.0, 4.6692568, 6283.07585], [34894.0, 4.6261, 12566.1517], [3497.0, 2.7441, 5753.3849], [3418.0, 2.8289, 3.5231], [3136.0, 3.6277, 77713.7715], [2676.0, 4.4181, 7860.4194], [2343.0, 6.1352, 3930.2097], [1324.0, 0.7425, 11506.7698], [1273.0, 2.0371, 529.691], [1199.0, 1.1096, 1577.3435], [990, 5.233, 5884.927], [902, 2.045, 26.298], [857, 3.508, 398.149], [780, 1.179, 5223.694], [753, 2.533, 5507.553], [505, 4.583, 18849.228], [492, 4.205, 775.523], [357, 2.92, 0.067], [317, 5.849, 11790.629], [284, 1.899, 796.298], [271, 0.315, 10977.079], [243, 0.345, 5486.778], [206, 4.806, 2544.314], [205, 1.869, 5573.143], [202, 2.458, 6069.777], [156, 0.833, 213.299], [132, 3.411, 2942.463], [126, 1.083, 20.775], [115, 0.645, 0.98], [103, 0.636, 4694.003], [102, 0.976, 15720.839], [102, 4.267, 7.114], [99, 6.21, 2146.17], [98, 0.68, 155.42], [86, 5.98, 161000.69], [85, 1.3, 6275.96], [85, 3.67, 71430.7], [80, 1.81, 17260.15], [79, 3.04, 12036.46], [75, 1.76, 5088.63], [74, 3.5, 3154.69], [74, 4.68, 801.82], [70, 0.83, 9437.76], [62, 3.98, 8827.39], [61, 1.82, 7084.9], [57, 2.78, 6286.6], [56, 4.39, 14143.5], [56, 3.47, 6279.55], [52, 0.19, 12139.55], [52, 1.33, 1748.02], [51, 0.28, 5856.48], [49, 0.49, 1194.45], [41, 5.37, 8429.24], [41, 2.4, 19651.05], [39, 6.17, 10447.39], [37, 6.04, 10213.29], [37, 2.57, 1059.38], [36, 1.71, 2352.87], [36, 1.78, 6812.77], [33, 0.59, 17789.85], [30, 0.44, 83996.85], [30, 2.74, 1349.87], [25, 3.16, 4690.48] ], [ [628331966747.0, 0, 0], [206059.0, 2.678235, 6283.07585], [4303.0, 2.6351, 12566.1517], [425.0, 1.59, 3.523], [119.0, 5.796, 26.298], [109.0, 2.966, 1577.344], [93, 2.59, 18849.23], [72, 1.14, 529.69], [68, 1.87, 398.15], [67, 4.41, 5507.55], [59, 2.89, 5223.69], [56, 2.17, 155.42], [45, 0.4, 796.3], [36, 0.47, 775.52], [29, 2.65, 7.11], [21, 5.34, 0.98], [19, 1.85, 5486.78], [19, 4.97, 213.3], [17, 2.99, 6275.96], [16, 0.03, 2544.31], [16, 1.43, 2146.17], [15, 1.21, 10977.08], [12, 2.83, 1748.02], [12, 3.26, 5088.63], [12, 5.27, 1194.45], [12, 2.08, 4694], [11, 0.77, 553.57], [10, 1.3, 6286.6], [10, 4.24, 1349.87], [9, 2.7, 242.73], [9, 5.64, 951.72], [8, 5.3, 2352.87], [6, 2.65, 9437.76], [6, 4.67, 4690.48] ], [ [52919.0, 0, 0], [8720.0, 1.0721, 6283.0758], [309.0, 0.867, 12566.152], [27, 0.05, 3.52], [16, 5.19, 26.3], [16, 3.68, 155.42], [10, 0.76, 18849.23], [9, 2.06, 77713.77], [7, 0.83, 775.52], [5, 4.66, 1577.34], [4, 1.03, 7.11], [4, 3.44, 5573.14], [3, 5.14, 796.3], [3, 6.05, 5507.55], [3, 1.19, 242.73], [3, 6.12, 529.69], [3, 0.31, 398.15], [3, 2.28, 553.57], [2, 4.38, 5223.69], [2, 3.75, 0.98] ], [ [289.0, 5.844, 6283.076], [35, 0, 0], [17, 5.49, 12566.15], [3, 5.2, 155.42], [1, 4.72, 3.52], [1, 5.3, 18849.23], [1, 5.97, 242.73] ], [ [114.0, 3.142, 0], [8, 4.13, 6283.08], [1, 3.84, 12566.15] ], [ [1, 3.14, 0] ] ]; var B_TERMS = [ [ [280.0, 3.199, 84334.662], [102.0, 5.422, 5507.553], [80, 3.88, 5223.69], [44, 3.7, 2352.87], [32, 4, 1577.34] ], [ [9, 3.9, 5507.55], [6, 1.73, 5223.69] ] ]; var R_TERMS = [ [ [100013989.0, 0, 0], [1670700.0, 3.0984635, 6283.07585], [13956.0, 3.05525, 12566.1517], [3084.0, 5.1985, 77713.7715], [1628.0, 1.1739, 5753.3849], [1576.0, 2.8469, 7860.4194], [925.0, 5.453, 11506.77], [542.0, 4.564, 3930.21], [472.0, 3.661, 5884.927], [346.0, 0.964, 5507.553], [329.0, 5.9, 5223.694], [307.0, 0.299, 5573.143], [243.0, 4.273, 11790.629], [212.0, 5.847, 1577.344], [186.0, 5.022, 10977.079], [175.0, 3.012, 18849.228], [110.0, 5.055, 5486.778], [98, 0.89, 6069.78], [86, 5.69, 15720.84], [86, 1.27, 161000.69], [65, 0.27, 17260.15], [63, 0.92, 529.69], [57, 2.01, 83996.85], [56, 5.24, 71430.7], [49, 3.25, 2544.31], [47, 2.58, 775.52], [45, 5.54, 9437.76], [43, 6.01, 6275.96], [39, 5.36, 4694], [38, 2.39, 8827.39], [37, 0.83, 19651.05], [37, 4.9, 12139.55], [36, 1.67, 12036.46], [35, 1.84, 2942.46], [33, 0.24, 7084.9], [32, 0.18, 5088.63], [32, 1.78, 398.15], [28, 1.21, 6286.6], [28, 1.9, 6279.55], [26, 4.59, 10447.39] ], [ [103019.0, 1.10749, 6283.07585], [1721.0, 1.0644, 12566.1517], [702.0, 3.142, 0], [32, 1.02, 18849.23], [31, 2.84, 5507.55], [25, 1.32, 5223.69], [18, 1.42, 1577.34], [10, 5.91, 10977.08], [9, 1.42, 6275.96], [9, 0.27, 5486.78] ], [ [4359.0, 5.7846, 6283.0758], [124.0, 5.579, 12566.152], [12, 3.14, 0], [9, 3.63, 77713.77], [6, 1.87, 5573.14], [3, 5.47, 18849.23] ], [ [145.0, 4.273, 6283.076], [7, 3.92, 12566.15] ], [ [4, 2.56, 6283.08] ] ]; //===================Periodic Terms for the nutation in longitude and obliquity=================== var Y_TERMS = [ [0, 0, 0, 0, 1], [-2, 0, 0, 2, 2], [0, 0, 0, 2, 2], [0, 0, 0, 0, 2], [0, 1, 0, 0, 0], [0, 0, 1, 0, 0], [-2, 1, 0, 2, 2], [0, 0, 0, 2, 1], [0, 0, 1, 2, 2], [-2, -1, 0, 2, 2], [-2, 0, 1, 0, 0], [-2, 0, 0, 2, 1], [0, 0, -1, 2, 2], [2, 0, 0, 0, 0], [0, 0, 1, 0, 1], [2, 0, -1, 2, 2], [0, 0, -1, 0, 1], [0, 0, 1, 2, 1], [-2, 0, 2, 0, 0], [0, 0, -2, 2, 1], [2, 0, 0, 2, 2], [0, 0, 2, 2, 2], [0, 0, 2, 0, 0], [-2, 0, 1, 2, 2], [0, 0, 0, 2, 0], [-2, 0, 0, 2, 0], [0, 0, -1, 2, 1], [0, 2, 0, 0, 0], [2, 0, -1, 0, 1], [-2, 2, 0, 2, 2], [0, 1, 0, 0, 1], [-2, 0, 1, 0, 1], [0, -1, 0, 0, 1], [0, 0, 2, -2, 0], [2, 0, -1, 2, 1], [2, 0, 1, 2, 2], [0, 1, 0, 2, 2], [-2, 1, 1, 0, 0], [0, -1, 0, 2, 2], [2, 0, 0, 2, 1], [2, 0, 1, 0, 0], [-2, 0, 2, 2, 2], [-2, 0, 1, 2, 1], [2, 0, -2, 0, 1], [2, 0, 0, 0, 1], [0, -1, 1, 0, 0], [-2, -1, 0, 2, 1], [-2, 0, 0, 0, 1], [0, 0, 2, 2, 1], [-2, 0, 2, 0, 1], [-2, 1, 0, 2, 1], [0, 0, 1, -2, 0], [-1, 0, 1, 0, 0], [-2, 1, 0, 0, 0], [1, 0, 0, 0, 0], [0, 0, 1, 2, 0], [0, 0, -2, 2, 2], [-1, -1, 1, 0, 0], [0, 1, 1, 0, 0], [0, -1, 1, 2, 2], [2, -1, -1, 2, 2], [0, 0, 3, 2, 2], [2, -1, 0, 2, 2], ]; var PE_TERMS = [ [-171996, -174.2, 92025, 8.9], [-13187, -1.6, 5736, -3.1], [-2274, -0.2, 977, -0.5], [2062, 0.2, -895, 0.5], [1426, -3.4, 54, -0.1], [712, 0.1, -7, 0], [-517, 1.2, 224, -0.6], [-386, -0.4, 200, 0], [-301, 0, 129, -0.1], [217, -0.5, -95, 0.3], [-158, 0, 0, 0], [129, 0.1, -70, 0], [123, 0, -53, 0], [63, 0, 0, 0], [63, 0.1, -33, 0], [-59, 0, 26, 0], [-58, -0.1, 32, 0], [-51, 0, 27, 0], [48, 0, 0, 0], [46, 0, -24, 0], [-38, 0, 16, 0], [-31, 0, 13, 0], [29, 0, 0, 0], [29, 0, -12, 0], [26, 0, 0, 0], [-22, 0, 0, 0], [21, 0, -10, 0], [17, -0.1, 0, 0], [16, 0, -8, 0], [-16, 0.1, 7, 0], [-15, 0, 9, 0], [-13, 0, 7, 0], [-12, 0, 6, 0], [11, 0, 0, 0], [-10, 0, 5, 0], [-8, 0, 3, 0], [7, 0, -3, 0], [-7, 0, 0, 0], [-7, 0, 3, 0], [-7, 0, 3, 0], [6, 0, 0, 0], [6, 0, -3, 0], [6, 0, -3, 0], [-6, 0, 3, 0], [-6, 0, 3, 0], [5, 0, 0, 0], [-5, 0, 3, 0], [-5, 0, 3, 0], [-5, 0, 3, 0], [4, 0, 0, 0], [4, 0, 0, 0], [4, 0, 0, 0], [-4, 0, 0, 0], [-4, 0, 0, 0], [-4, 0, 0, 0], [3, 0, 0, 0], [-3, 0, 0, 0], [-3, 0, 0, 0], [-3, 0, 0, 0], [-3, 0, 0, 0], [-3, 0, 0, 0], [-3, 0, 0, 0], [-3, 0, 0, 0], ]; //=================== Utility functions for other applications (such as NREL's SAMPA) -------------- function deg2rad(degrees) { return (PI / 180.0) * degrees; } exports.deg2rad = deg2rad; function rad2deg(radians) { return (180.0 / PI) * radians; } exports.rad2deg = rad2deg; function limit_degrees(degrees) { degrees /= 360; var limited = 360 * (degrees - Math.floor(degrees)); if (limited < 0) { limited += 360; } return limited; } exports.limit_degrees = limit_degrees; function third_order_polynomial(a, b, c, d, x) { return ((a * x + b) + c) * x + d; } exports.third_order_polynomial = third_order_polynomial; function geocentric_right_ascension(lamda, epsilon, beta) { var lambdaRad = deg2rad(lamda); var epsilonRad = deg2rad(epsilon); return limit_degrees(rad2deg(Math.atan2(Math.sin(lambdaRad) * Math.cos(epsilonRad) - Math.tan(deg2rad(beta)) * Math.sin(epsilonRad), Math.cos(lambdaRad)))); } exports.geocentric_right_ascension = geocentric_right_ascension; function geocentric_declination(beta, epsilon, lamda) { var betaRad = deg2rad(beta); var epsilonRad = deg2rad(epsilon); return rad2deg(Math.asin(Math.sin(betaRad) * Math.cos(epsilonRad) + Math.cos(betaRad) * Math.sin(epsilonRad) * Math.sin(deg2rad(lamda)))); } exports.geocentric_declination = geocentric_declination; function observer_hour_angle(nu, longitude, alpha_deg) { return limit_degrees(nu + longitude - alpha_deg); } exports.observer_hour_angle = observer_hour_angle; function right_ascension_parallax_and_topocentric_dec(latitude, elevation, xi, h, delta, dltap) { var delta_alpha_rad = 0; var lat_rad = deg2rad(latitude); var xi_rad = deg2rad(xi); var h_rad = deg2rad(h); var delta_rad = deg2rad(delta); var u = Math.atan(0.99664719 * Math.tan(lat_rad)); var y = 0.99664719 * Math.sin(u) + elevation * Math.sin(lat_rad) / 6378140.0; var x = Math.cos(u) + elevation * Math.cos(lat_rad) / 6378140.0; delta_alpha_rad = Math.atan2(-x * Math.sin(xi_rad) * Math.sin(h_rad), Math.cos(delta_rad) - x * Math.sin(xi_rad) * Math.cos(h_rad)); dltap.delta_prime = rad2deg(Math.atan2((Math.sin(delta_rad) - y * Math.sin(xi_rad)) * Math.cos(delta_alpha_rad), Math.cos(delta_rad) - x * Math.sin(xi_rad) * Math.cos(h_rad))); dltap.delta_alpha = rad2deg(delta_alpha_rad); } exports.right_ascension_parallax_and_topocentric_dec = right_ascension_parallax_and_topocentric_dec; function topocentric_right_ascension(alpha_deg, delta_alpha) { return alpha_deg + delta_alpha; } exports.topocentric_right_ascension = topocentric_right_ascension; function topocentric_local_hour_angle(h, delta_alpha) { return h - delta_alpha; } exports.topocentric_local_hour_angle = topocentric_local_hour_angle; function topocentric_elevation_angle(latitude, delta_prime, h_prime) { var latRad = deg2rad(latitude); var deltaPrimeRad = deg2rad(delta_prime); return rad2deg(Math.asin(Math.sin(latRad) * Math.sin(deltaPrimeRad) + Math.cos(latRad) * Math.cos(deltaPrimeRad) * Math.cos(deg2rad(h_prime)))); } exports.topocentric_elevation_angle = topocentric_elevation_angle; function atmospheric_refraction_correction(pressure, temperature, atmos_refract, e0) { var delE = 0; if (e0 >= -1 * (SUN_RADIUS + atmos_refract)) delE = (pressure / 1010.0) * (283.0 / (273.0 + temperature)) * 1.02 / (60.0 * Math.tan(deg2rad(e0 + 10.3 / (e0 + 5.11)))); return delE; } exports.atmospheric_refraction_correction = atmospheric_refraction_correction; function topocentric_elevation_angle_corrected(e0, delta_e) { return e0 + delta_e; } exports.topocentric_elevation_angle_corrected = topocentric_elevation_angle_corrected; function topocentric_zenith_angle(e) { return 90.0 - e; } exports.topocentric_zenith_angle = topocentric_zenith_angle; function topocentric_azimuth_angle_astro(h_prime, latitude, delta_prime) { var h_prime_rad = deg2rad(h_prime); var lat_rad = deg2rad(latitude); return limit_degrees(rad2deg(Math.atan2(Math.sin(h_prime_rad), Math.cos(h_prime_rad) * Math.sin(lat_rad) - Math.tan(deg2rad(delta_prime)) * Math.cos(lat_rad)))); } exports.topocentric_azimuth_angle_astro = topocentric_azimuth_angle_astro; function topocentric_azimuth_angle(azimuth_astro) { return limit_degrees(azimuth_astro + 180.0); } exports.topocentric_azimuth_angle = topocentric_azimuth_angle; //=================== Local Utility functions =================== function integer(val) { return Math.floor(val); } //=============================================================== function validate_inputs(spa) { if ((spa.year < -2000) || (spa.year > 6000)) return 1; if ((spa.month < 1) || (spa.month > 12)) return 2; if ((spa.day < 1) || (spa.day > 31)) return 3; if ((spa.hour < 0) || (spa.hour > 24)) return 4; if ((spa.minute < 0) || (spa.minute > 59)) return 5; if ((spa.second < 0) || (spa.second >= 60)) return 6; if ((spa.pressure < 0) || (spa.pressure > 5000)) return 12; if ((spa.temperature <= -273) || (spa.temperature > 6000)) return 13; if ((spa.delta_ut1 <= -1) || (spa.delta_ut1 >= 1)) return 17; if ((spa.hour == 24) && (spa.minute > 0)) return 5; if ((spa.hour == 24) && (spa.second > 0)) return 6; if (Math.abs(spa.delta_t) > 8000) return 7; if (Math.abs(spa.timezone) > 18) return 8; if (Math.abs(spa.longitude) > 180) return 9; if (Math.abs(spa.latitude) > 90) return 10; if (Math.abs(spa.atmos_refract) > 5) return 16; if (spa.elevation < -6500000) return 11; return 0; } //=============================================================== function julian_day(year, month, day, hour, minute, second, dut1, tz) { var day_decimal = 0.0; var julian_day = 0.0; var a = 0.0; day_decimal = day + (hour - tz + (minute + (second + dut1) / 60.0) / 60.0) / 24.0; if (month < 3) { month += 12; year--; } julian_day = integer(365.25 * (year + 4716.0)) + integer(30.6001 * (month + 1)) + day_decimal - 1524.5; if (julian_day > 2299160.0) { a = integer(year / 100); julian_day += (2 - a + integer(a / 4)); } return julian_day; } function julian_century(jd) { return (jd - 2451545.0) / 36525.0; } function mean_elongation_moon_sun(jce) { return third_order_polynomial(1.0 / 189474.0, -0.0019142, 445267.11148, 297.85036, jce); } function julian_ephemeris_day(jd, delta_t) { return jd + delta_t / 86400.0; } function julian_ephemeris_century(jde) { return (jde - 2451545.0) / 36525.0; } function julian_ephemeris_millennium(jce) { return (jce / 10.0); } function earth_periodic_term_summation(terms, count, jme) { var sum = 0; for (var i = 0; i < count; i++) sum += terms[i][TermsA.TERM_A] * Math.cos(terms[i][TermsA.TERM_B] + terms[i][TermsA.TERM_C] * jme); return sum; } function earth_values(term_sum, count, jme) { var sum = 0; for (var i = 0; i < count; i++) sum += term_sum[i] * Math.pow(jme, i); sum /= 1.0e8; return sum; } function earth_heliocentric_longitude(jme) { var sum = []; for (var i = 0; i < L_COUNT; i++) sum[i] = earth_periodic_term_summation(L_TERMS[i], l_subcount[i], jme); return limit_degrees(rad2deg(earth_values(sum, L_COUNT, jme))); } function earth_heliocentric_latitude(jme) { var sum = []; for (var i = 0; i < B_COUNT; i++) sum[i] = earth_periodic_term_summation(B_TERMS[i], b_subcount[i], jme); return rad2deg(earth_values(sum, B_COUNT, jme)); } function earth_radius_vector(jme) { var sum = []; for (var i = 0; i < R_COUNT; i++) sum[i] = earth_periodic_term_summation(R_TERMS[i], r_subcount[i], jme); return earth_values(sum, R_COUNT, jme); } function geocentric_longitude(l) { var theta = l + 180.0; if (theta >= 360.0) theta -= 360.0; return theta; } function geocentric_latitude(b) { return -b; } function mean_anomaly_sun(jce) { return third_order_polynomial(-1.0 / 300000.0, -0.0001603, 35999.05034, 357.52772, jce); } function mean_anomaly_moon(jce) { return third_order_polynomial(1.0 / 56250.0, 0.0086972, 477198.867398, 134.96298, jce); } function argument_latitude_moon(jce) { return third_order_polynomial(1.0 / 327270.0, -0.0036825, 483202.017538, 93.27191, jce); } function ascending_longitude_moon(jce) { return third_order_polynomial(1.0 / 450000.0, 0.0020708, -1934.136261, 125.04452, jce); } function xy_term_summation(i, x) { var sum = 0; for (var j = 0; j < TERM_Y_COUNT; j++) sum += x[j] * Y_TERMS[i][j]; return sum; } function nutation_longitude_and_obliquity(jce, x, spa) { var xy_term_sum; var sum_psi = 0; var sum_epsilon = 0; for (var i = 0; i < Y_COUNT; i++) { xy_term_sum = deg2rad(xy_term_summation(i, x)); sum_psi += (PE_TERMS[i][TermsPE.TERM_PSI_A] + jce * PE_TERMS[i][TermsPE.TERM_PSI_B]) * Math.sin(xy_term_sum); sum_epsilon += (PE_TERMS[i][TermsPE.TERM_EPS_C] + jce * PE_TERMS[i][TermsPE.TERM_EPS_D]) * Math.cos(xy_term_sum); } spa.del_psi = sum_psi / 36000000.0; spa.del_epsilon = sum_epsilon / 36000000.0; } function ecliptic_mean_obliquity(jme) { var u = jme / 10.0; return 84381.448 + u * (-4680.93 + u * (-1.55 + u * (1999.25 + u * (-51.38 + u * (-249.67 + u * (-39.05 + u * (7.12 + u * (27.87 + u * (5.79 + u * 2.45))))))))); } function ecliptic_true_obliquity(delta_epsilon, epsilon0) { return delta_epsilon + epsilon0 / 3600.0; } function aberration_correction(r) { return -20.4898 / (3600.0 * r); } function apparent_sun_longitude(theta, delta_psi, delta_tau) { return theta + delta_psi + delta_tau; } function greenwich_mean_sidereal_time(jd, jc) { return limit_degrees(280.46061837 + 360.98564736629 * (jd - 2451545.0) + jc * jc * (0.000387933 - jc / 38710000.0)); } function greenwich_sidereal_time(nu0, delta_psi, epsilon) { return nu0 + delta_psi * Math.cos(deg2rad(epsilon)); } function sun_equatorial_horizontal_parallax(r) { return 8.794 / (3600.0 * r); } function surface_incidence_angle(zenith, azimuth_astro, azm_rotation, slope) { var zenith_rad = deg2rad(zenith); var slope_rad = deg2rad(slope); return rad2deg(Math.acos(Math.cos(zenith_rad) * Math.cos(slope_rad) + Math.sin(slope_rad) * Math.sin(zenith_rad) * Math.cos(deg2rad(azimuth_astro - azm_rotation)))); } function sun_mean_longitude(jme) { return limit_degrees(280.4664567 + jme * (360007.6982779 + jme * (0.03032028 + jme * (1 / 49931.0 + jme * (-1 / 15300.0 + jme * (-1 / 2000000.0)))))); } function limit_minutes(minutes) { var limited = minutes; if (limited < -20.0) limited += 1440.0; else if (limited > 20.0) limited -= 1440.0; return limited; } function eot(m, alpha, del_psi, epsilon) { return limit_minutes(4.0 * (m - 0.0057183 - alpha + del_psi * Math.cos(deg2rad(epsilon)))); } function approx_sun_transit_time(alpha_zero, longitude, nu) { return (alpha_zero - longitude - nu) / 360.0; } function sun_hour_angle_at_rise_set(latitude, delta_zero, h0_prime) { var h0 = -99999; var latitude_rad = deg2rad(latitude); var delta_zero_rad = deg2rad(delta_zero); var argument = (Math.sin(deg2rad(h0_prime)) - Math.sin(latitude_rad) * Math.sin(delta_zero_rad)) / (Math.cos(latitude_rad) * Math.cos(delta_zero_rad)); if (Math.abs(argument) <= 1) h0 = limit_degrees180(rad2deg(Math.acos(argument))); return h0; } function limit_zero2one(value) { var limited = value - Math.floor(value); if (limited < 0) limited += 1.0; return limited; } function approx_sun_rise_and_set(m_rts, h0) { var h0_dfrac = h0 / 360.0; m_rts[SunState.SUN_RISE] = limit_zero2one(m_rts[SunState.SUN_TRANSIT] - h0_dfrac); m_rts[SunState.SUN_SET] = limit_zero2one(m_rts[SunState.SUN_TRANSIT] + h0_dfrac); m_rts[SunState.SUN_TRANSIT] = limit_zero2one(m_rts[SunState.SUN_TRANSIT]); } function rts_alpha_delta_prime(ad, n) { var a = ad[JDSign.JD_ZERO] - ad[JDSign.JD_MINUS]; var b = ad[JDSign.JD_PLUS] - ad[JDSign.JD_ZERO]; if (Math.abs(a) >= 2.0) a = limit_zero2one(a); if (Math.abs(b) >= 2.0) b = limit_zero2one(b); return ad[JDSign.JD_ZERO] + n * (a + b + (b - a) * n) / 2.0; } function limit_degrees180pm(degrees) { var limited; degrees /= 360.0; limited = 360.0 * (degrees - Math.floor(degrees)); if (limited < -180.0) limited += 360.0; else if (limited > 180.0) limited -= 360.0; return limited; } function limit_degrees180(degrees) { var limited; degrees /= 180.0; limited = 180.0 * (degrees - Math.floor(degrees)); if (limited < 0) limited += 180.0; return limited; } function rts_sun_altitude(latitude, delta_prime, h_prime) { var latitude_rad = deg2rad(latitude); var delta_prime_rad = deg2rad(delta_prime); return rad2deg(Math.asin(Math.sin(latitude_rad) * Math.sin(delta_prime_rad) + Math.cos(latitude_rad) * Math.cos(delta_prime_rad) * Math.cos(deg2rad(h_prime)))); } function sun_rise_and_set(m_rts, h_rts, delta_prime, latitude, h_prime, h0_prime, sun) { return m_rts[sun] + (h_rts[sun] - h0_prime) / (360.0 * Math.cos(deg2rad(delta_prime[sun])) * Math.cos(deg2rad(latitude)) * Math.sin(deg2rad(h_prime[sun]))); } function dayfrac_to_local_hr(dayfrac, timezone) { return 24.0 * limit_zero2one(dayfrac + timezone / 24.0); } //////////////////////////////////////////////////////////////////////// // Calculate Equation of Time (EOT) and Sun Rise, Transit, & Set (RTS) //////////////////////////////////////////////////////////////////////// function calculate_eot_and_sun_rise_transit_set(spa) { var nu = 0; var m = 0; var h0 = 0; var n = 0; var alpha = []; var delta = []; var m_rts = []; var nu_rts = []; var h_rts = []; var alpha_prime = []; var delta_prime = []; var h_prime = []; var h0_prime = -1 * (SUN_RADIUS + spa.atmos_refract); var sun_rts = copySPA(spa); sun_rts.hour = sun_rts.minute = sun_rts.second = 0; sun_rts.delta_ut1 = sun_rts.timezone = 0.0; sun_rts.jd = julian_day(sun_rts.year, sun_rts.month, sun_rts.day, sun_rts.hour, sun_rts.minute, sun_rts.second, sun_rts.delta_ut1, sun_rts.timezone); m = sun_mean_longitude(spa.jme); spa.eot = eot(m, spa.alpha, spa.del_psi, spa.epsilon); calculate_geocentric_sun_right_ascension_and_declination(sun_rts); nu = sun_rts.nu; sun_rts.delta_t = 0; sun_rts.jd--; for (var i = 0; i < JDSign.JD_COUNT; i++) { calculate_geocentric_sun_right_ascension_and_declination(sun_rts); alpha[i] = sun_rts.alpha; delta[i] = sun_rts.delta; sun_rts.jd++; } m_rts[SunState.SUN_TRANSIT] = approx_sun_transit_time(alpha[JDSign.JD_ZERO], spa.longitude, nu); h0 = sun_hour_angle_at_rise_set(spa.latitude, delta[JDSign.JD_ZERO], h0_prime); if (h0 >= 0) { approx_sun_rise_and_set(m_rts, h0); for (var i = 0; i < SunState.SUN_COUNT; i++) { nu_rts[i] = nu + 360.985647 * m_rts[i]; n = m_rts[i] + spa.delta_t / 86400.0; alpha_prime[i] = rts_alpha_delta_prime(alpha, n); delta_prime[i] = rts_alpha_delta_prime(delta, n); h_prime[i] = limit_degrees180pm(nu_rts[i] + spa.longitude - alpha_prime[i]); h_rts[i] = rts_sun_altitude(spa.latitude, delta_prime[i], h_prime[i]); } spa.srha = h_prime[SunState.SUN_RISE]; spa.ssha = h_prime[SunState.SUN_SET]; spa.sta = h_rts[SunState.SUN_TRANSIT]; spa.suntransit = dayfrac_to_local_hr(m_rts[SunState.SUN_TRANSIT] - h_prime[SunState.SUN_TRANSIT] / 360.0, spa.timezone); spa.sunrise = dayfrac_to_local_hr(sun_rise_and_set(m_rts, h_rts, delta_prime, spa.latitude, h_prime, h0_prime, SunState.SUN_RISE), spa.timezone); spa.sunset = dayfrac_to_local_hr(sun_rise_and_set(m_rts, h_rts, delta_prime, spa.latitude, h_prime, h0_prime, SunState.SUN_SET), spa.timezone); } else spa.srha = spa.ssha = spa.sta = spa.suntransit = spa.sunrise = spa.sunset = -99999; } //////////////////////////////////////////////////////////////////////////////////////////////// // Calculate required SPA parameters to get the right ascension (alpha) and declination (delta) // Note: JD must be already calculated and in structure //////////////////////////////////////////////////////////////////////////////////////////////// function calculate_geocentric_sun_right_ascension_and_declination(spa) { spa.jc = julian_century(spa.jd); spa.jde = julian_ephemeris_day(spa.jd, spa.delta_t); spa.jce = julian_ephemeris_century(spa.jde); spa.jme = julian_ephemeris_millennium(spa.jce); spa.l = earth_heliocentric_longitude(spa.jme); spa.b = earth_heliocentric_latitude(spa.jme); spa.r = earth_radius_vector(spa.jme); spa.theta = geocentric_longitude(spa.l); spa.beta = geocentric_latitude(spa.b); var x = []; x[TermsX.TERM_X0] = spa.x0 = mean_elongation_moon_sun(spa.jce); x[TermsX.TERM_X1] = spa.x1 = mean_anomaly_sun(spa.jce); x[TermsX.TERM_X2] = spa.x2 = mean_anomaly_moon(spa.jce); x[TermsX.TERM_X3] = spa.x3 = argument_latitude_moon(spa.jce); x[TermsX.TERM_X4] = spa.x4 = ascending_longitude_moon(spa.jce); nutation_longitude_and_obliquity(spa.jce, x, spa); spa.epsilon0 = ecliptic_mean_obliquity(spa.jme); spa.epsilon = ecliptic_true_obliquity(spa.del_epsilon, spa.epsilon0); spa.del_tau = aberration_correction(spa.r); spa.lamda = apparent_sun_longitude(spa.theta, spa.del_psi, spa.del_tau); spa.nu0 = greenwich_mean_sidereal_time(spa.jd, spa.jc); spa.nu = greenwich_sidereal_time(spa.nu0, spa.del_psi, spa.epsilon); spa.alpha = geocentric_right_ascension(spa.lamda, spa.epsilon, spa.beta); spa.delta = geocentric_declination(spa.beta, spa.epsilon, spa.lamda); } //Calculate SPA output values (in structure) based on input values passed in structure function spa_calculate(spa) { var result = validate_inputs(spa); if (result == 0) { spa.jd = julian_day(spa.year, spa.month, spa.day, spa.hour, spa.minute, spa.second, spa.delta_ut1, spa.timezone); calculate_geocentric_sun_right_ascension_and_declination(spa); spa.h = observer_hour_angle(spa.nu, spa.longitude, spa.alpha); spa.xi = sun_equatorial_horizontal_parallax(spa.r); var dltap = { delta_alpha: spa.del_alpha, delta_prime: spa.delta_prime }; right_ascension_parallax_and_topocentric_dec(spa.latitude, spa.elevation, spa.xi, spa.h, spa.delta, dltap); spa.del_alpha = dltap.delta_alpha; spa.delta_prime = dltap.delta_prime; spa.alpha_prime = topocentric_right_ascension(spa.alpha, spa.del_alpha); spa.h_prime = topocentric_local_hour_angle(spa.h, spa.del_alpha); spa.e0 = topocentric_elevation_angle(spa.latitude, spa.delta_prime, spa.h_prime); spa.del_e = atmospheric_refraction_correction(spa.pressure, spa.temperature, spa.atmos_refract, spa.e0); spa.e = topocentric_elevation_angle_corrected(spa.e0, spa.del_e); spa.zenith = topocentric_zenith_angle(spa.e); spa.azimuth_astro = topocentric_azimuth_angle_astro(spa.h_prime, spa.latitude, spa.delta_prime); spa.azimuth = topocentric_azimuth_angle(spa.azimuth_astro); if ((spa.function == exports.SPA_ZA_INC) || (spa.function == exports.SPA_ALL)) spa.incidence = surface_incidence_angle(spa.zenith, spa.azimuth_astro, spa.azm_rotation, spa.slope); if ((spa.function == exports.SPA_ZA_RTS) || (spa.function == exports.SPA_ALL)) calculate_eot_and_sun_rise_transit_set(spa); } return result; } exports.spa_calculate = spa_calculate;