ABSTRACT:Routines to calculate ephemeris
C ROUTINE CALLED: atMoonPhase in atEphemeris.c
Compute the phase of the moon (0.0 = new, 1.0 = full) formula from Jean Meeus's Astronomical Formula for Calculators, 3rd Edition, pp. 155). This routine was originally called illuminated_fraction.
TCL SYNTAX: moonPhase "<long>" "<lat>" "<sun>" TCL HELP STRING: Find the phase of the moon. TCL ARGUMENTS: : "<long>" : Moon's ecliptic longitude (degrees) "<lat>" : Moon's ecliptic latitude (degrees) "<sun>" : Sun's longitude (degrees)
C ROUTINE CALLED: atRiseSet in atEphemeris.c
Returns the local time of rise or set for an object with the specified ra and dec, at a site with the specified latitide and longitude and time zone, for the given Julian epoch. Rising and setting are defined with respect to the specified zenith distance. Returns -1 if object doesn't rise or set (formula from Astronomical Formulae for Calculators, 3rd edition, Jean Meeus, p. 47 and Astronomical Almanac 1989, p. A12).
TCL SYNTAX: riseSet "<ra>" "<dec>" "<long>" "<lat>" "<epoch>" "<timezone>" "<zenithdist>" "<which>" TCL HELP STRING: Return local rise/set time. TCL ARGUMENTS: : "<ra>" : Right ascension (degrees) "<dec>" : declination (degrees) "<long>" : Earth west longitude (degrees) "<lat>" : Earth latitude (degrees) "<epoch>" : Julian epoch "<timezone>" : Time zone "<zenithdist>" : Zenith distance defining rising and setting "<which>" : Which phenomenom (RISE or SET)
C ROUTINE CALLED: atMjdRiseSet in atEphemeris.c
Returns the local time of rise or set for an object with the specified ra and dec, at a site with the specified latitide and longitude and time zone, for the given Julian epoch. Rising and setting are defined with respect to the specified zenith distance. Returns -1 if object doesn't rise or set (formula from Astronomical Formulae for Calculators, 3rd edition, Jean Meeus, p. 47 and Astronomical Almanac 1989, p. A12).
TCL SYNTAX: mjdRiseSet "<ra>" "<dec>" "<longitude>" "<lat>" "<mjd>" "<timezone>" "<zenithdist>" "<which>" TCL HELP STRING: Return local rise/set time. TCL ARGUMENTS: : "<ra>" : Right ascension (degrees) "<dec>" : declination (degrees) "<longitude>" : Earth west longitude (degrees) "<lat>" : Earth latitude (degrees) "<mjd>" : Modified Julian date "<timezone>" : Time zone "<zenithdist>" : Zenith distance defining rising and setting "<which>" : Which phenomenom (RISE or SET)
C ROUTINE CALLED: atHourAngle in atEphemeris.c
atHourAngle -- Returns the hour angle (in degrees) for the specified declination, earth latitide, and zenith distance. Returns -1 if no solution (object never reaches that hour angle). Formula from Astronomical Formulae for Calculators, 3rd edition, Jean Meeus, p. 47.
TCL SYNTAX: hourAngle "<zenithdist>" "<dec>" "<lat>" TCL HELP STRING: Find hour angle TCL ARGUMENTS: : "<zenithdist>" : Zenith distance (degrees from pole) "<dec>" : declination (degrees) "<lat>" : Earth latitude (degrees)
C ROUTINE CALLED: atNextNewMoon in atEphemeris.c
Start at the time given in beginTime, and step by deltaHours. The TSTAMP returned is the time of the first minimum of the separation between the moon and the Sun. deltaHours defaults to 1 hour.
TCL SYNTAX: nextNewMoon "<beginTime>" "-deltaHours" TCL HELP STRING: Find next new moon TCL ARGUMENTS: : "<beginTime>" : Beginning time "-deltaHours" : time step in hours
C ROUTINE CALLED: atNextFullMoon in atEphemeris.c
Start at the time given in beginTime, and step by deltaHours. The TSTAMP returned is the time of the first minimum of the separation between the moon and the Sun. deltaHours defaults to 1 hour.
TCL SYNTAX: nextFullMoon "<beginTime>" "-deltaHours" TCL HELP STRING: Find next Full moon TCL ARGUMENTS: : "<beginTime>" : Beginning time "-deltaHours" : time step in hours