Beyond

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This library was started to better understand how Flight Dynamics works. It has no intent of efficiency nor performance at the moment, and the goal is mainly to develop a simple API for space observations.

The sources of this library can be found at github <https://github.com/galactics/beyond>__ and are under the MIT license.

Installation

Beyond requires Python 3.6+, numpy and sgp4 <https://github.com/brandon-rhodes/python-sgp4>__. To install the library and its dependencies use pip

.. code-block:: shell

pip install beyond

Documentation

• Last release <http://beyond.readthedocs.io/en/stable/>__ (stable)
• Dev <http://beyond.readthedocs.io/en/latest/>__ (latest)

Usage

.. code-block:: python

import numpy as np
from beyond.io.tle import Tle
from beyond.frames import create_station
from beyond.dates import Date, timedelta

# Parse TLE
tle = Tle("""ISS (ZARYA)
1 25544U 98067A   19072.15347313  .00000167  00000-0  10147-4 0  9997
2 25544  51.6420 118.6717 0004098  99.2855 123.2259 15.52799885160336""")

# Create a station from which to compute the pass
station = create_station('KSC', (28.524058, -80.65085, 0.0))

for orb in station.visibility(tle.orbit(), start=Date.now(), stop=timedelta(days=1), step=timedelta(minutes=2), events=True):

    # As all angles are given in radians,
    # there is some conversion to do
    azim = -np.degrees(orb.theta) % 360
    elev = np.degrees(orb.phi)
    r = orb.r / 1000.

    print("{event:10} {tle.name}  {date:%Y-%m-%dT%H:%M:%S.%f} {azim:7.2f} {elev:7.2f} {r:10.2f}".format(
        date=orb.date, r=r, azim=azim, elev=elev,
        tle=tle, event=orb.event if orb.event is not None else ""
    ))

    # Stop at the end of the first pass
    if orb.event and orb.event.info == "LOS":
        break

This library is used as basis for the Space-Command <https://github.com/galactics/space-command>__ utility.

Commons usages for this library are:

• Predicting of satellite visibility <http://beyond.readthedocs.io/en/stable//examples.html#station-pointings>__
• Computing satellite ground track <http://beyond.readthedocs.io/en/stable//examples.html#ground-track>__
• Computing planets visibility <http://beyond.readthedocs.io/en/stable//examples.html#jupiter-and-its-moons>__

References

A lot of the formulas and flight dynamic algorithm are based on Vallado's Fundamentals of Astrodynamic and Applications 4th ed.