Planets

#!/usr/bin/env python3

import astropy.units as u
from astropy.time import Time
from astropy.coordinates import get_body, AltAz, EarthLocation
from subprocess import run

def direction(az):
	'Return a string indication of the azimuth (given in degrees).'

	dirs = 'N NNE NE ENE E ESE SE SSE S SSW SW WSW W WNW NW NNW'.split()
	i = int(((az + 11.25) % 360) / 22.5)
	return dirs[i]

# Current time in UTC.
ut = Time.now()

# Observation location.
# This is currently set to the Visitor Center at the Morton Arboretum in
# Lisle, Illinois, which is probably not where you'll be viewing the sky.
# Change the latitude and longitude to your viewing location. The values
# must be in decimal degrees followed by `*.u.deg`. The height parameter
# is optional.
loc = EarthLocation(lat=41.81433*u.deg, lon=-88.07093*u.deg, height=208*u.m)

# Bodies of interest.
planets = 'Moon Sun Mercury Venus Mars Jupiter Saturn'.split()

# Current positions of all the bodies.
pos = {}
const = {}
for p in planets:
    pos[p] = get_body(p, ut).transform_to(AltAz(obstime=ut, location=loc))
    const[p] = pos[p].get_constellation()

# Assemble the results.
output = []
for p in planets:
    output.append(f'{p:>8s}: {pos[p].az.value:3.0f} \
{direction(pos[p].az.value):3s} {pos[p].alt.value:3.0f} {const[p]}')

# Pipe the results through TerminalWidget. The widget that gets the results
# must be named "planets." You can change the colors and font, but make
# sure the font you choose is monospaced.
tw = '/Applications/TerminalWidget.app/Contents/MacOS/TerminalWidget\
 --target planets --font Menlo --bg eeeeee --fg 000000 --text -'.split()
run(tw, input='\n'.join(output).encode())

# To send the output to a terminal instead of TerminalWidget, comment the
# three lines above and uncomment the line below. This may aid in debugging.
# print('\n'.join(output))