spacerocks is a Python package that puts the solar system at your fingertips.
It provides high-level abstractions
for orbital dynamics and solar system observations. Its modern,
expressive API makes it extremely easy to define orbits, work
with multiple objects (bound or unbound), transform coordinates,
numerically propagate orbits, and compute precise ephemerides.
There is support for arbitrary rotation curves, and much more.
The most computationally expensive tasks are written in C and wrapped with Python. Under the hood, the code uses rebound for numerical integration and spiceypy for reading spice files, making the computations fast and the results robust.
Here we illustrate the accuracy of the calculations by comparing
our predicted ephemerides of Ceres to those generated by JPL Horizons
for a 50 year timespan. The calculation takes only a few lines
of code in spacerocks.
from spacerocks import SpaceRock, Units
from astropy.time import Time
import numpy as np
rock = SpaceRock.from_horizons(name='Ceres')
startdate = Time('2000-01-01', scale='utc', format='iso')
enddate = Time('2050-01-01', scale='utc', format='iso')
testdates = Time(np.arange(startdate.jd, enddate.jd, 30), scale='utc', format='jd')
units = Units()
units.timescale = 'utc'
prop, planets, sim = rock.propagate(epochs=testdates.jd, model='PLANETS', units=units)
obs = prop.observe(obscode='W84')
The spacerocks prediction never differs from the JPL Horizons prediction by more than half an arcsecond.
Several common use cases are illustrated in tutorial notebooks. One that I find rather useful is a subclass of rebound's
Simulation class. See a short tutorial here. For more information, see the documentation. The SpaceRock doc is a good place to start.
The easiest way to install spacerocks is with pip:
pip install spacerocksIf you want to be sure that you have the most up-to-date version, you can clone the repository and install from the source.
git clone https://github.com/kjnapier/spacerocks.git
cd spacerocks
python setup.py build_ext -i
pip install .You'll also need OpenMP and swig. On MacOS, you can install these with brew
brew install libomp
brew install swig