CalSky

{{Short description|Web-based astronomical calculator}}

CalSky (sky calendar) was a web-based astronomical calculator used by astronomers to plan observing. It was created by Arnold Barmettler, a researcher at the University of Zurich and formerly a scientific assistant at the European Space Agency.{{Cite web |url=http://www.barmettler.com/prof.html |title=Arnold Barmettler |access-date=2011-06-17 |archive-url=https://web.archive.org/web/20110720193512/http://www.barmettler.com/prof.html |archive-date=2011-07-20 |url-status=dead }} The website, available in English and German, featured a calendar (and/or email notifications) generated for your location including information on aurora, comets, tides, solar and lunar eclipses, planets, bright satellite passes (ISS, HST, etc.), occultations, transits, satellite flares, and decaying satellites that may be visible.{{cite book|last=(editor)|first=Günter D. Roth|title=Handbook of practical astronomy|date=2009|publisher=Springer|location=Berlin|isbn=978-3-540-76377-2|pages=420|edition=Rev.}}{{cite journal|author=Zimbabwe Scientific Association|journal=The Zimbabwe Science News|volume=33|pages=61}}{{cite journal|journal=Astronomy Now|date=2005|volume=19|series=7-12|pages=33}} In October 2020, the original website ceased operations. However, a replacement website is being run by Arnold Barmettler with the URL calsky.io.