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itself is +22.8°, corresponding to sunrise around Jun 4–8 and Jul 6–10 (in the
Gregorian calendar);
• December solstice sunrise occurred at an easily identifiable point on the horizon,
a discernible dip to the left of a small isolated peak, distant 55.93 km at 114°
azimuth. This dip has 113.6° azimuth, 3.6° altitude and −23.8° declination, so
the December sun would have risen directly out from this dip;
• A prominent dip, 50.08 km away in the mountainous horizon to the east, the lowest point on this distant ridge, at the intersection of two mountain ranges, coincides with sunrise at the two equinoxes. The bottom of the dip has −0.15°
declination: at the astronomical equinox, the sun spans −0.25° to +0.25°
declination; and,
• There is no obvious feature on the horizon marking ‘zenith sunrise’ (sunrise on
the days when the sun passes across the zenith at noon, an event of significance
among various tropical cultures in the Americas), which occurs at −8.55° declination over the horizon 49.03 km away.
Regarding other prominent features on the horizon itself:
• At azimuth 103°–105° and 49.88 km away, there is a prominent ‘half-moon’shaped dip within the highest part of the horizon, with yet more distant horizon
rising to a rounded peak beyond: this has attracted attention as a possible
foresight. The declination range, −13.5° to −15.2°, corresponds to sunrise
between approximately February 7–12 and October 27–November 1 (in the
Gregorian calendar);
• At azimuth 106.5°–107.5°, distant 42.88–42.96 km, again within the highest part
of the horizon, there is a feature resembling a stepped pyramid, which has also
attracted attention as a possible foresight. The declination range here, −17.0°
(peak) down to −17.8° (bottom of right-hand slope), corresponds to sunrise
between approximately January 29–31 and November 8–10 (in the Gregorian
calendar).
In any natural horizon used as a solar horizon calendar, the features and foresights available to provide accurate markers of sunrise on certain dates are positioned, in effect, randomly, although the dates when the sun rises behind them may
acquire cultural significance as a consequence (Ruggles, 2014: 24–25). In the case
of Chankillo, the most prominent horizon notch coincides precisely with the position of equinoctial sunrise, as viewed from the entrance to the Temple of the Pillars.
Notwithstanding that there is much specialist discussion about the precise definition
and cultural significance of the equinox (Ruggles, 2017), it strongly suggests that
this location acquired cultural significance as the appropriate viewing point, and
was therefore chosen as the site of the Temple of the Pillars. It is also likely that this
spectacular mountainous profile, with a variety of other features that would have
provided natural foresights marking the changing rising position of the sun, provided a precursor of, and inspiration for, the construction and use of the towers for
this purpose.
I. Ghezzi
itself is +22.8°, corresponding to sunrise around Jun 4–8 and Jul 6–10 (in the
Gregorian calendar);
• December solstice sunrise occurred at an easily identifiable point on the horizon,
a discernible dip to the left of a small isolated peak, distant 55.93 km at 114°
azimuth. This dip has 113.6° azimuth, 3.6° altitude and −23.8° declination, so
the December sun would have risen directly out from this dip;
• A prominent dip, 50.08 km away in the mountainous horizon to the east, the lowest point on this distant ridge, at the intersection of two mountain ranges, coincides with sunrise at the two equinoxes. The bottom of the dip has −0.15°
declination: at the astronomical equinox, the sun spans −0.25° to +0.25°
declination; and,
• There is no obvious feature on the horizon marking ‘zenith sunrise’ (sunrise on
the days when the sun passes across the zenith at noon, an event of significance
among various tropical cultures in the Americas), which occurs at −8.55° declination over the horizon 49.03 km away.
Regarding other prominent features on the horizon itself:
• At azimuth 103°–105° and 49.88 km away, there is a prominent ‘half-moon’shaped dip within the highest part of the horizon, with yet more distant horizon
rising to a rounded peak beyond: this has attracted attention as a possible
foresight. The declination range, −13.5° to −15.2°, corresponds to sunrise
between approximately February 7–12 and October 27–November 1 (in the
Gregorian calendar);
• At azimuth 106.5°–107.5°, distant 42.88–42.96 km, again within the highest part
of the horizon, there is a feature resembling a stepped pyramid, which has also
attracted attention as a possible foresight. The declination range here, −17.0°
(peak) down to −17.8° (bottom of right-hand slope), corresponds to sunrise
between approximately January 29–31 and November 8–10 (in the Gregorian
calendar).
In any natural horizon used as a solar horizon calendar, the features and foresights available to provide accurate markers of sunrise on certain dates are positioned, in effect, randomly, although the dates when the sun rises behind them may
acquire cultural significance as a consequence (Ruggles, 2014: 24–25). In the case
of Chankillo, the most prominent horizon notch coincides precisely with the position of equinoctial sunrise, as viewed from the entrance to the Temple of the Pillars.
Notwithstanding that there is much specialist discussion about the precise definition
and cultural significance of the equinox (Ruggles, 2017), it strongly suggests that
this location acquired cultural significance as the appropriate viewing point, and
was therefore chosen as the site of the Temple of the Pillars. It is also likely that this
spectacular mountainous profile, with a variety of other features that would have
provided natural foresights marking the changing rising position of the sun, provided a precursor of, and inspiration for, the construction and use of the towers for
this purpose.
I. Ghezzi