ktrio3/orbital-drift

A program to graph the coordinates of the planets over a given time frame

Developer's Notes

This project was developed as part of a reseach-focused honors course at the University of South Florida I took Fall 2016; it has been sitting untouched on a private bitbucket repo since then. I have left the documentation and code exactly as it was when the class ended, including the report (having been away from the project, I didn't want to remove/edit an important piece of documentation).

Disclaimer: I am not an astronomer or physicist, and any results of this program should not be used for anything more than trivial curiosity.

Obrital_Drift.py

I ran and developed this program on Ubuntu 16.0.4

Currently, I am unaware of any bugs that prevent the program from running, and have tested all of the below examples.

Input that is not identified as either a planet or command will be ignored. Note that options that recquire a follow up argument or a particular format will error out or cause odd behavior if these conditions are not met. (i.e. -c requires an argument, and -d and -e require dates formatted as YYYY-MM-DD, etc.)

The only package that needs to be installed is Plotly, which is available through pip.

Plotly may spit out some warning messages during execution, but all of the messages I have encountered can be safely ignored for the offline mode used for this project. (Unfortunately, Plotly provides no means of silencing or changing the messages it outputs.+)

On completion, Plotly will print a message to stdout (after a new prompt has appeared), and will open the file in the default web browser. I used Chrome during testing. In some cases, this causes errors to be output to the terminal, but these are typically from the browser, and all of the errors I have seen are handled by it, and can be ignored.

An internet connection is necessary to use the Horizon options. Typically, there are no issues connecting. I did have trouble on a network at another university that blocked telnet for guest users.

The VSOP87 method can take about a minute to run for a single planet for a year. The other two methods typically take less than a couple seconds to run.

Examples

Below are several different example commands that can be run to test out the orbital drift program.

A complete list of the available options and explanations of their purpose can be found in the report.

Graphs Earth, Venus, and Mars using the Schlyter and Horizon methods.

./orbital_drift.py E V Ma -gh

Graphs Earth, Venus, and Mars using the Schlyter, VSOP87 and Horizon methods.

./orbital_drift.py E V Ma -vs E V Ma -gh

Saves report of the differences between planet calculations to "out.txt", without graphing

./orbital_drift.py E V Ma -vs E V Ma -gh -o out.txt -ng

Graphs Earth with a timer for the program

./orbital_drift.py E -t

Graphs Earth from January 1st, 2001 to January 22nd, 2001

./orbital_drift.py E -d 2001-01-01 -e 2001-01-22

Graph the Sun and Mars using geocentric coordinates.

./orbital_drift.py M -g

Graphs only Mars and Earth using geocentric coordinates.

./orbital_drift.py M E -g -n

Graphs the Earth and Sun using Mars as the center.

./orbital_drift.py E -c M