predict.py

#!/usr/bin/env python3

import ephem
from math import degrees
from datetime import datetime

class Observer(ephem.Observer):
    def __init__(self, name, lat, lon, elevation):
        super().__init__()
        self.name, self.lat, self.lon, self.elevation = (
                name, str(lat), str(lon), elevation)

def read_tle(lines):
    return ephem.readtle(*lines)

def time_fmt(et):
    return datetime(*map(int, et.tuple())).strftime('%Y-%m-%d %H.%M.%S')

obs = Observer('ESOC', 49.8542, 8.625, 135)

# https://celestrak.com/NORAD/elements/stations.txt
sat = read_tle('''\
SWISSCUBE               
1 35932U 09051B   18035.40447406  .00000096  00000-0  32613-4 0  9997
2 35932  98.5241 183.5296 0006635 254.5696 105.4768 14.56117004444118\
'''.split('\n'))
n = 10


print('listing %d next passes of %s from %s (%.2fN %.2fE)' % (
            n, sat.name.strip(), obs.name, degrees(obs.lat), degrees(obs.lon)))
print('---------------------------------------------------------')
print('AOS                   az      LOS                   az')
print('---------------------------------------------------------')
for _ in range(n):
    aos, aos_az, tca, alt, los, los_az = obs.next_pass(sat)
    obs.date = los + ephem.minute
    print('%s | %5.1f | %s | %5.1f' % (time_fmt(aos), degrees(aos_az), 
                                       time_fmt(los), degrees(los_az)))
print('---------------------------------------------------------')