This repository contains PHP and Javascript libraries useful for astronomical calculations. Since the Earth is an astronomical body too (surprise!) and many astronomical calculations require geographical parameters, a good amount of geographical libraries are included as well.
PHP libraries are stored in the libs-php directory, Javascript libraries in the libs-js directory. There are examples how to use each of the libraries in the corresponding examples-xxx directories. This is built in the form of a little website, the entry point being index.html in the root directory. A live version can be found at https://astronomy-libs.mpopp.net
In most cases, PHP and Javascript libraries with the same name (e.g. Coordinates.php and coordinates.js) are (mostly) equivalents of each other, but there may be exceptions.
These libraries deliberately support only recent technology. For PHP libraries and examples, Apache 2.2+ and PHP 5.3+ are required. Supported browsers are Firefox, Google Chrome, Internet Explorer and Opera in their current versions on Linux, Windows and Android (as available).
Contributions are very welcome. Feel free to fork, fix bugs, improve libraries and examples, write new libraries and examples, redesign, do whatever comes to mind. Pull requests are appreciated.
Coordinates contains functions to convert float coordinates (geographical latitude/longitude or astronomical RE/DE coordinates) to text representation and vice versa.
Distances contains functions to convert distance units, like kilometers, miles, astronomical units, light years and parsecs. Another function calculates the geographical distance between 2 latitude/longitude pairs (on Earth), yet another function calculates the distance between 2 points while the distance to each of the points and the angle separating is given.
Location (geographical latitude & longitude) contains a wrapper to provide a uniform format to be used by other libraries.
The Javascript version also contains a function to obtain the geographical location using the Geolocation API
Simbard provides methods to query the SIMBAD Astronomical Database (http://simbad.u-strasbg.fr/simbad/) using their web services at http://cdsws.u-strasbg.fr/axis/services/Sesame?wsdl