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Sidera Noctis Calendar

Annual Rise & Set Chart

Acquiring GPS…

— ⟳ Computing…

Important Dates — — Elongations · Oppositions · Meteor Showers · Culminations

—Computing…

Attribution & Notes — Sidera Noctis · Calendar

Celestial Mechanics: All rise, transit, and set times follow Jean Meeus, Astronomical Algorithms, 2nd ed. (Willmann-Bell, 1998). Solar twilight boundaries use binary bisection on solar altitude. Planet positions use a simplified low-order orbital-element model following Meeus Ch. 31–33, derived from but not implementing the full VSOP87 series (Bretagnon & Francou 1988). Moon positions use the 23-term longitude / 14-term latitude series from Meeus Ch. 47.

DSO Visibility: Deep-sky object positions are J2000 catalog coordinates. Arcs show times when the object is above 15° altitude (a practical observing threshold). Precession is not applied (~0.35° drift over 25 years, acceptable for this chart).

Chart Convention: X-axis shows local time centered on midnight (approximately 17:00–09:00 the following day). Y-axis spans January through December of the selected year. The shaded band shows daytime (Sun above horizon). The dark fill marks the astronomical twilight zone (Sun between −18° and the horizon).

Important Dates: Meteor shower peak dates are fixed annual values. Planetary elongation and opposition dates are computed by scanning daily geocentric ecliptic longitude differences. DSO optimal viewing dates are the nights when the Sun's right ascension is 12 hours from the object's RA (object transits at midnight).

This page is intended for personal, educational, and citizen-science use only. No warranty is expressed or implied regarding the accuracy of any displayed values.

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