plot_exotica_ephemerides.py

#!/usr/bin/env python

from astroquery.jplhorizons import Horizons
from datetime import datetime, timedelta
import pylab as plt

srclist = [
    '2015 BZ509',
    '2011 SP25',
    '2017 RR2',
    '2017 SV13',
    '2018 TL6',
    'A/2017 U1',
    '1989 UH2',
    '2015 TG387',
    '2012 VP113',
    '2018 VG18',
    '2014 MU69',
    '1999 RQ36'
    ]

now = datetime.utcnow()
now_p14 = now + timedelta(days=14)

timespan = {
    'start': now.strftime('%Y-%m-%d'),
    'stop':  now_p14.strftime('%Y-%m-%d'),
    'step':  '1d'
    }

sun  = Horizons(10, epochs=timespan, id_type='majorbody')
moon = Horizons(301, epochs=timespan, id_type='majorbody')

# Calculate ephemerides
eph, ras, decs, horzns = [], [], [], []
for srcname in srclist:
    print srcname
      src = Horizons(srcname, epochs=timespan)
    e = src.ephemerides()
    horzns.append(src)
    eph.append(e)
    ras.append(e['RA'][0] / 360.0 * 24)
    decs.append(e['DEC'][0])

# Calculate sun and moon ephemerides
e_sun = sun.ephemerides()
e_moon = moon.ephemerides()


# Plot
plt.scatter(ras, decs)
for sn, r, d in zip(srclist, ras, decs):
    plt.annotate(sn, xy=(r, d))

plt.scatter([e_sun['RA'][0] / 360.0 * 24,],  [e_sun['DEC'][0],], c='#cc0000')
plt.scatter([e_moon['RA'][0] / 360.0 * 24,], [e_moon['DEC'][0],], c='#cc0000')
plt.annotate('Sun', xy=(e_sun['RA'][0] / 360.0 * 24, e_sun['DEC'][0]))
plt.annotate('Moon', xy=(e_moon['RA'][0] / 360.0 * 24, e_moon['DEC'][0]))

# Label plots
plt.title("Object ephemerides {d}".format(d=now.strftime('%Y-%m-%d')))
plt.xlabel("RA [hr]")
plt.ylabel("DEC [deg]")
plt.xlim(0, 24)
plt.xticks(range(0, 24+1, 4))
plt.minorticks_on()
plt.show()