def apparent_planet_pos(planet_name, tdb, site):
'''Return the topocentric apparent position (ra, dec) tuple of a planet at
a particular time, from a particular site.
Thin wrapper for SLA_RDPLAN.
'''
latitude = site['latitude']
longitude = site['longitude']
# TODO: Raise an error if an invalid body is provided.
planet = dict(mercury=1,
venus=2,
moon=3,
mars=4,
jupiter=5,
saturn=6,
uranus=7,
neptune=8,
pluto=9,
sun=0)
(app_ra_rads, app_dec_rads,
diameter_rads) = sla.sla_rdplan(tdb, planet[planet_name],
longitude.in_radians(),
latitude.in_radians())
app_ra = Angle(radians=app_ra_rads)
app_dec = Angle(radians=app_dec_rads)
diameter = Angle(radians=diameter_rads)
return (app_ra, app_dec, diameter)
def calcPos(self, mjd, config):
"""Calculate the moon's ecliptic lon/lat and geocentric RA/Dec, for the given MJD(s)."""
self.mjd = numpy.copy(mjd)
self.ra = numpy.zeros(len(mjd), 'float')
self.dec = numpy.zeros(len(mjd), 'float')
for i in range(len(mjd)):
# Calculate moon's position.
ra_RAD, dec_RAD, diam = slalib.sla_rdplan(mjd[i], 3,
config['longitude']*_deg2rad, config['latitude']*_deg2rad)
self.ra[i] = ra_RAD * _rad2deg
self.dec[i] = dec_RAD * _rad2deg
# Calculate the lunar phase.
eclon = numpy.zeros(len(mjd), 'float')
eclat = numpy.zeros(len(mjd), 'float')
for i in range(len(mjd)):
eclon[i], eclat[i] = slalib.sla_eqecl(self.ra[i]*_deg2rad, self.dec[i]*_deg2rad, self.mjd[i])
# Calculate the solar longitude.
sun = Sun()
lon_sun = sun.getLon(self.mjd)*_deg2rad
# Calculate the solar elongation of the Moon.
solarelong = numpy.arccos(numpy.cos((lon_sun - eclon)) * numpy.cos(eclat))
# Calculate the phase of the moon. This is the 0-180 degrees phase.
self.phase = 180.0 - solarelong*_rad2deg
# Calculate the illumination of the Moon. This is between 0 - 100, and is what Opsim calls 'moonPhase'.
self.illum = ( 1 + numpy.cos(self.phase*_deg2rad) )/2.0 * 100.0
return
def calcPos(self, mjd, config):
"""Calculate the moon's ecliptic lon/lat and geocentric RA/Dec, for the given MJD(s)."""
self.mjd = numpy.copy(mjd)
self.ra = numpy.zeros(len(mjd), 'float')
self.dec = numpy.zeros(len(mjd), 'float')
for i in range(len(mjd)):
# Calculate moon's position.
ra_RAD, dec_RAD, diam = slalib.sla_rdplan(
mjd[i], 3, config['longitude'] * _deg2rad,
config['latitude'] * _deg2rad)
self.ra[i] = ra_RAD * _rad2deg
self.dec[i] = dec_RAD * _rad2deg
# Calculate the lunar phase.
eclon = numpy.zeros(len(mjd), 'float')
eclat = numpy.zeros(len(mjd), 'float')
for i in range(len(mjd)):
eclon[i], eclat[i] = slalib.sla_eqecl(self.ra[i] * _deg2rad,
self.dec[i] * _deg2rad,
self.mjd[i])
# Calculate the solar longitude.
sun = Sun()
lon_sun = sun.getLon(self.mjd) * _deg2rad
# Calculate the solar elongation of the Moon.
solarelong = numpy.arccos(
numpy.cos((lon_sun - eclon)) * numpy.cos(eclat))
# Calculate the phase of the moon. This is the 0-180 degrees phase.
self.phase = 180.0 - solarelong * _rad2deg
# Calculate the illumination of the Moon. This is between 0 - 100, and is what Opsim calls 'moonPhase'.
self.illum = (1 + numpy.cos(self.phase * _deg2rad)) / 2.0 * 100.0
return
def test_HJD_to_JD():
event = _create_event()
parallax_model = ['None', 1664.51]
parallax = microlparallax.MLParallaxes(event, parallax_model)
JD = 2455000
MJD = JD- 2400000.5
Sun_angles = slalib.sla_rdplan(MJD,99,0,0)
HJD = JD - parallax.AU/parallax.speed_of_light*(np.sin(Sun_angles[1])*np.sin(event.dec*np.pi/180)+
np.cos(Sun_angles[1])*np.cos(event.dec*np.pi/180)*
np.cos(event.ra*np.pi/180-Sun_angles[0]))
jd = parallax.HJD_to_JD([HJD])
np.allclose(jd,JD)
def test_HJD_to_JD():
event = _create_event()
parallax_model = ['None', 1664.51]
parallax = microlparallax.MLParallaxes(event, parallax_model)
JD = 2455000
MJD = JD- 2400000.5
Sun_angles = slalib.sla_rdplan(MJD,99,0,0)
HJD = JD - parallax.AU/parallax.speed_of_light*(np.sin(Sun_angles[1])*np.sin(event.dec*np.pi/180)+
np.cos(Sun_angles[1])*np.cos(event.dec*np.pi/180)*
np.cos(event.ra*np.pi/180-Sun_angles[0]))
jd = parallax.HJD_to_JD([HJD])
np.allclose(jd,JD)
def findNightDuration(mjd):
ctio_lat = -30.16527778
ctio_lon = -70.8125
ctio_height = 2215.
degToRad = 2. * np.pi / 360.
lat = ctio_lat * degToRad
lon = ctio_lon * degToRad
height = ctio_height
imjd = np.int(mjd)
start_mjd = imjd - 6. / 24.
# before sunset at CTIO
sunset = ""
sunrise = ""
# check every minute
for i in np.arange(0, 1., 1. / (24. * 60)):
mjd = start_mjd + i
gmst = slalib.sla_gmst(mjd)
eqEquinoxes = slalib.sla_eqeqx(mjd)
lst = gmst + eqEquinoxes + lon
sunra, sundec, diam = slalib.sla_rdplan(mjd, 0, lon, lat)
sunha = lst - sunra
sinAltRad = np.sin(lat)*np.sin(sundec) + \
np.cos(lat)*np.cos(sundec)*np.cos(sunha)
altRad = np.arcsin(sinAltRad)
zenithDist = 90 * degToRad - altRad
twilight = 100. * 2 * np.pi / 360.
if zenithDist <= twilight:
bright = True
else:
bright = False
if sunset == "" and bright == False:
sunset = mjd
if sunset != "" and sunrise == "" and bright == True:
sunrise = mjd
duration = sunrise - sunset
return duration, sunset, sunrise
def getSolarPosition(self, mjd, eastLongitude, latitude, lst):
ra, dec, diam = slalib.sla_rdplan(mjd, 0, eastLongitude, latitude)
ha = lst - ra
zd = self.zenithDistance(ha, dec, latitude)
return ra, dec, zd
