This is a description for the back-end of a website which tells you whether or not Mercury is in retrograde. This project is dedicated to Olivia. This project has been developed by jakewilliami and andfield.
- Ephemeris
- What am I reading?
- Contents
- How to set up this project
- What is retrograde motion?
- Calculation and Generation of Ephemerides
- Room for improvement
Our dependency for Flask is that you have Python 3.3+. You need to check this is installed:
python[3] --version
Now download your virtual environment toolbox:
pip[3] install virtualenv
cd to your project directory and run
python[3] -m venv <project-name>
virtualenv <project-name>
source <project-name>/bin/activate
Now we need to set up flask and get our dependencies. Run
pip[3] install -r requirements.txt
And you are set up. Run python[3] app.py to get the local server running. Non-local server is currently in progress. You can run deactivate to escape your virtual environment.
Within one's personal computer, one can access wonders.
We have found four very excellent and open-source repositories that have helped us to determine this critical question:
- A Python library developed by Brandon Rhodes. This library provides mathematical tools (used by the Jet Propulsion Laboratory to calculate their ephemerides) to predict raw planetary positions in three-dimensional space.
- A Python library developed by skyfielders. This library sources data from the United States Naval Observatory and the International Earth Rotation Service, and used the above repository in its calculations.
- A python library also developed by Brandon Rhodes. This library is specifically focussed on the Scientific calculations for Atronomy.
- A Julia library provided by JuliaAstro. This is based on the former-mentioned repository, and provides a Julia implementation of these mathematical and astronomical tools.
With the help of these excellent resources, we have managed to calculate whether or not Mercury is in retrograde.
Ensure you have Julia downloaded and installed. We have created a virtual environment in alt/astro-alt.jl/. To use this on your machine, run
$ cd is-mercury-in-retrograde/alt/astro-alt.jl/
$ julia
julia> ]
pkg> activate .
(astro-alt.jl) instantiate
To run the project, you will need to specify the project directory:
$ cd is-mercury-in-retrograde/alt/astro-alt.jl/
$ julia --project=. astro-alt.jl
See the manual for more information on this.
Finally, you need to download the data file:
$ cd is-mercury-in-retrograde/alt/astro-alt.jl/
$ wget https://naif.jpl.nasa.gov/pub/naif/generic_kernels/spk/planets/de430.bsp # for the JPLEphemeris package
$ wget ftp://ftp.imcce.fr/pub/ephem/planets/inpop13c/inpop13c_TDB_m100_p100_tt.dat # for the CALCEPH package
There is room for improvement. Within the script astro.py and astro-alt.py, we have defined two points in time by defining one, waiting, and defining another. This is undoubtably not the best way to do this, but this was the only way I found that works. In the early drafts of the script, we would define a time t1 which is five seconds before the current time, but this did not work for some reason. We would always be open for any help on this.
- Create request for user accessing website to give back-end user's timezone for python calculations.
- Work on pyinstaller standalone executiable for any server.
- Work on frontend