def test_position_of_radec():
epsilon = _GIGAPARSEC_AU * 1e-16
p = api.position_of_radec(0, 0)
assert length_of(p.position.au - [_GIGAPARSEC_AU, 0, 0]) < epsilon
p = api.position_of_radec(6, 0)
assert length_of(p.position.au - [0, _GIGAPARSEC_AU, 0]) < epsilon
epsilon = 2e-16
p = api.position_of_radec(12, 90, 2)
assert length_of(p.position.au - [0, 0, 2]) < epsilon
p = api.position_of_radec(12, 90, distance_au=2)
assert length_of(p.position.au - [0, 0, 2]) < epsilon
ts = api.load.timescale()
epoch = ts.tt_jd(api.B1950)
p = api.position_of_radec(0, 0, 1, epoch=epoch)
assert length_of(p.position.au - [1, 0, 0]) > 1e-16
ra, dec, distance = p.radec(epoch=epoch)
assert abs(ra.hours) < 1e-12
assert abs(dec.degrees) < 1e-12
assert abs(distance.au - 1) < 1e-16
def test_constellations():
lookup = load_constellation_map()
assert lookup(position_of_radec(0, 0)) == 'Psc'
assert lookup(position_of_radec(360, 90)) == 'UMi'
# (4.65, 0) used to be in Orion, but, precession
assert lookup(position_of_radec(4.65, 0)) == 'Eri'
assert lookup(position_of_radec(4.75, 0.3)) == 'Ori'
# Test vectorization.
assert list(lookup(position_of_radec([4.65, 4.75],
[0, 0.3]))) == ['Eri', 'Ori']
def test_constellations():
ts = load.timescale(builtin=True)
t = ts.utc(2000)
lookup = load_constellation_map()
assert lookup(position_of_radec(0, 0)) == 'Psc'
assert lookup(position_of_radec(360, 90)) == 'UMi'
# (4.65, 0) used to be in Orion, but, precession
assert lookup(position_of_radec(4.65, 0)) == 'Eri'
assert lookup(position_of_radec(4.75, 0.3)) == 'Ori'
# Test vectorization.
assert (lookup(position_of_radec([4.65, 4.75],
[0, 0.3])) == ['Eri', 'Ori']).all()
def test_constellations():
lookup = load_constellation_map()
assert lookup(position_of_radec(0, 0)) == 'Psc'
assert lookup(position_of_radec(360, 90)) == 'UMi'
# (4.65, 0) used to be in Orion, but, precession
assert lookup(position_of_radec(4.65, 0)) == 'Eri'
assert lookup(position_of_radec(4.75, 0.3)) == 'Ori'
# exploit extend() bug, issue 547
B1875 = Time(None, julian_date_of_besselian_epoch(1875))
assert lookup(position_of_radec(18.1747, 39., epoch=B1875)) == 'Her'
assert lookup(position_of_radec(18.1753, 39., epoch=B1875)) == 'Lyr'
# Test vectorization.
assert list(
lookup(position_of_radec([4.65, 4.75], [0, 0.3]))
) == ['Eri', 'Ori']
int(month),
int(date),
int(hour),
int(mins),
tzinfo=tz)
t1 = dt.astimezone(pytz.utc)
ts = api.load.timescale()
y, m, d, h, mns = t1.year, t1.month, t1.date, t1.hour, t1.minute
t = ts.utc(y, m, h, mns)
topos = api.Topos(latitude_degrees=lat, longitude_degrees=lon)
observer = topos.at(t)
pos = observer.from_altaz(alt_degrees=alt, az_degrees=azi)
ra, dec, distance = pos.radec()
constellation_at = load_constellation_map()
coord = position_of_radec(ra.hours, dec.degrees)
print(constellation_at(coord))
print("RA = ", ra)
print("Dec = ", dec)
t2 = (2020, 11, 14, 22, 00)
topos = api.Topos(latitude_degrees=31.77,
longitude_degrees=76.98) #coordinates of iit mandi
observer = topos.at(t)
pos = observer.from_altaz(alt_degrees=90, az_degrees=0)
ra, dec, distance = pos.radec()
constellation_at = load_constellation_map()
coord = position_of_radec(ra.hours, dec.degrees)
print("Constellation right above Lucy: ", constellation_at(coord))
pos = observer.from_altaz(alt_degrees=270, az_degrees=0)
#100K times between 2022 and 2024
n_steps = 10000
jdrange = np.linspace(2459690.5,2460055.75,n_steps)
utrange = ts.ut1_jd(jdrange)
utrange._nutation_angles = iau2000b(utrange.tt)
#Crab Nebula
target_ra = 83.63308333
target_dec = 22.0145
#My RA is in degrees, hence the division by 15.
target_pos = position_of_radec(target_ra / 15., target_dec)
#Currently not optimized for speed
bool_list = []
t_list = []
for this_ut in tqdm.tqdm(utrange):
this_bool = this_sat.is_target_occulted(this_ut, target_pos, earth)
dist_intersect = this_sat.intersect_line_with_sphere(this_ut, target_pos, earth)
t_list.append(dist_intersect)
bool_list.append(this_bool)
bool_mask = np.array(bool_list)
t_arr = np.array(t_list)
t_bool1 = np.isfinite(t_arr)
"""Compute the tilt of Saturn, for planetary_magnitude()."""
from skyfield.api import position_of_radec
# pc = PlanetaryConstants()
# pc.read_text(load('pck00008.tpc'))
# TODO: Figure out how to extract this from "pck00008.tpc". For now,
# these values are copied and pasted.
BODY699_POLE_RA = 40.589
BODY699_POLE_DEC = 83.537
p = position_of_radec(BODY699_POLE_RA / 15.0, BODY699_POLE_DEC, 1.0).xyz.au
print('Saturn:', p)
BODY799_POLE_RA = 257.311
BODY799_POLE_DEC = -15.175
p = position_of_radec(BODY799_POLE_RA / 15.0, BODY799_POLE_DEC, 1.0).xyz.au
print('Uranus:', p)