The tritos is an

eclipse cycle Eclipses may occur repeatedly, separated by certain intervals of time: these intervals are called eclipse cycles. The series of eclipses separated by a repeat of one of these intervals is called an eclipse series. Eclipse conditions Eclipses ...

of 3,986.628 days (about 10 years, 11 months). It corresponds to: *135

synodic month In lunar calendars, a lunar month is the time between two successive Syzygy (astronomy), syzygies of the same type: new moons or full moons. The precise definition varies, especially for the beginning of the month. Variations In Shona people, S ...

s *146.50144

draconic month In lunar calendars, a lunar month is the time between two successive syzygies of the same type: new moons or full moons. The precise definition varies, especially for the beginning of the month. Variations In Shona, Middle Eastern, and Europ ...

s *11.50144 eclipse years (23

eclipse season An eclipse season is a period, roughly every six months, when eclipses occur. Eclipse seasons are the result of the axial parallelism of the Orbit of the Moon, Moon's orbital plane (orbital inclination, tilted five degrees to the ecliptic, Earth ...

s) *144.68135

anomalistic month In lunar calendars, a lunar month is the time between two successive syzygies of the same type: new moons or full moons. The precise definition varies, especially for the beginning of the month. Variations In Shona, Middle Eastern, and Euro ...

s. The length of the tritos is equal to the length of the

inex The inex (plural ''inexes'') is an eclipse cycle of 10,571.95 days (about 29 years minus 20 days). The cycle was first described in modern times by Crommelin in 1901, but was named by George van den Bergh who studied it in detail half a century la ...

minus the length of the saros eclipse cycles. Therefore, eclipses that occur 1 tritos apart (i.e. both eclipses belong to the same tritos series), belong to two different saros series with series numbers that differ by one. The

pre-Columbian In the history of the Americas, the pre-Columbian era, also known as the pre-contact era, or as the pre-Cabraline era specifically in Brazil, spans from the initial peopling of the Americas in the Upper Paleolithic to the onset of European col ...

Maya Maya may refer to: Ethnic groups * Maya peoples, of southern Mexico and northern Central America ** Maya civilization, the historical civilization of the Maya peoples ** Mayan languages, the languages of the Maya peoples * Maya (East Africa), a p ...

used a calculation in their own observations of eclipse cycles in which a period of three tritoses (or tritoi) was approximated by 11960 days, based on 46 periods of their tzolk'in calendar (i.e. 46 × 260 days). The number of ''anomalistic months'' in a tritos (144.68), having a fraction near , means every third eclipse is in nearly the same position in the elliptical orbit, so eclipses will have similar timing and total versus annular quality. Solar and lunar eclipse event dates will repeat on this cycle for about 700 years.

Example solar Tritos series

Example lunar Tritos series

{{July 2000 lunar eclipse Tritos series

References

* Mathematical Astronomy Morsels, Jean Meeus, Willmann-Bell, Inc., 1997 (Chapter 9, p. 51, Table 9.A Some eclipse Periodicities) Eclipses

Example solar Tritos series

Example lunar Tritos series

See also

References