Astronomical algorithms used in the app are taken from the book Astronomical Algorithms (2nd edition) by Jean Meeus and from Astronomy on the Personal Computer (4th edition) by Oliver Montenbruck and Thomas Pfleger.
Distance to horizon calculation, considering refraction, based on the formula given by Andrew. T. Young.
All Eclipse information from NASA website. Eclipse Predictions by Fred Espenak, NASA/GSFC Emeritus.
Clustering algorithm for grouping the pins in the POIs view is based on the algorithm of Applidium.
Magnetic declination is calculated using the World Magnetic Model WMM2015.
The NPF Rule to figure out the maximum exposure time to get stars as spots was developed by Frédéric Michaud for the Société Astronomique du Havre.
Time zone and altitude data obtained from geonames.org.
Points of Interest linked to Wikipedia and Panoramio websites.
Eclipse KML files by Xavier M. Jubier.
HUD (head-up display) indicator based on Matej Bukovinski code, available on GitHub.
Sun eclipse photo by Oregon State University.
KML file importer/exporter uses KML.Framework. Copyright (c) 2012 NextBusinessSystem Co., Ltd. All rights reserved.
The MIT License (MIT); this license applies to GeographicLib,
versions 1.12 and later.
Copyright (c) 2008-2017, Charles Karney
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files (the "Software"), to deal in the Software without
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of the Software, and to permit persons to whom the Software is
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