12
equinox?’ (Ruggles, 1997). In this work, he established the difference between the
true astronomical equinox (δ = 0°), when the sun crosses the celestial equator, the day
midway between the two solstices, sunrise at due-East, or the mid- horizon sunrise
point between solstice sunrises, among other possible definitions. All of them were
near the same point on the horizon where sunrise occurs but could represent quite different concepts in the worldview of the builders under scrutiny.
The concept of equinox (from the Latin ‘equal night’, meaning the day when the
length of the day and night are equivalent) has a precise meaning within the framework of classical spherical astronomy—derived from Greek sources—that underline our Western religious and scientific tradition. From the scientific point of view,
the equinox is the instant when the sun, moving along the ecliptic, crosses the celestial equator and has a declination of 0°. The day of the equinox (either spring or
autumn) is considered as the day when this fact happens. Alternatively, the preceding sunrise and subsequent sunset (or vice versa when it occurs at night) could be
termed the equinoctial sunrise and sunset, respectively.
A culture’s understanding of the equinox can be teased out from how they used
that concept. For instance, a decade after Clive’s question, González-García and
Belmonte (2006) asked themselves ‘Which equinox?’ when the date and concept of
the equinox in ancient Rome at the time of the Julian reform had to be taken into
account. The Romans apparently favoured the day midway between the solstices
instead of the astronomical equinox itself. This could have obvious consequences
when interpreting the archaeoastronomical data of the Roman era as we will later
demonstrate. As the reader can imagine, from the perspective of a totally different
worldview, finding a concept similar to Western equinox would be far from simple,
and as Clive argued, and will be proved later on, ‘it could make no sense at all’
(Ruggles, 1997).
In the following section, a diachronic, geographic approach to different cultural
environments somehow related to our Western world, from the hill of Göbekli Tepe
to the Christian churches of the Iberian Peninsula, will be performed, seeking for
what could have been the exact meaning of equinox and how a people approached
it. This will be completed with a few sketches of alien cultures where this concept
has also been claimed. Finally, in the conclusion we will concentrate on how reliable the concept of equinox is and if it still deserves to be preserved in cultural
astronomy studies, including archaeoastronomy and ethnoastronomy.
2 Discussion: Which Equinox?
Until recent times, the megalithic monuments in Europe were the archaeological
remains earning all the credit for any potential astronomical knowledge of the earliest ancestors of humankind. However, a discovery in southeast Anatolia has changed
these ideas. There, on a barren isolated hill called Göbekli Tepe, a team of German
and Turkish archaeologists (see Schmidt, 2006 for the discovery) have been
excavating a cluster of suggestive cyclopean monuments erected with large, megaJ. A. Belmonte
equinox?’ (Ruggles, 1997). In this work, he established the difference between the
true astronomical equinox (δ = 0°), when the sun crosses the celestial equator, the day
midway between the two solstices, sunrise at due-East, or the mid- horizon sunrise
point between solstice sunrises, among other possible definitions. All of them were
near the same point on the horizon where sunrise occurs but could represent quite different concepts in the worldview of the builders under scrutiny.
The concept of equinox (from the Latin ‘equal night’, meaning the day when the
length of the day and night are equivalent) has a precise meaning within the framework of classical spherical astronomy—derived from Greek sources—that underline our Western religious and scientific tradition. From the scientific point of view,
the equinox is the instant when the sun, moving along the ecliptic, crosses the celestial equator and has a declination of 0°. The day of the equinox (either spring or
autumn) is considered as the day when this fact happens. Alternatively, the preceding sunrise and subsequent sunset (or vice versa when it occurs at night) could be
termed the equinoctial sunrise and sunset, respectively.
A culture’s understanding of the equinox can be teased out from how they used
that concept. For instance, a decade after Clive’s question, González-García and
Belmonte (2006) asked themselves ‘Which equinox?’ when the date and concept of
the equinox in ancient Rome at the time of the Julian reform had to be taken into
account. The Romans apparently favoured the day midway between the solstices
instead of the astronomical equinox itself. This could have obvious consequences
when interpreting the archaeoastronomical data of the Roman era as we will later
demonstrate. As the reader can imagine, from the perspective of a totally different
worldview, finding a concept similar to Western equinox would be far from simple,
and as Clive argued, and will be proved later on, ‘it could make no sense at all’
(Ruggles, 1997).
In the following section, a diachronic, geographic approach to different cultural
environments somehow related to our Western world, from the hill of Göbekli Tepe
to the Christian churches of the Iberian Peninsula, will be performed, seeking for
what could have been the exact meaning of equinox and how a people approached
it. This will be completed with a few sketches of alien cultures where this concept
has also been claimed. Finally, in the conclusion we will concentrate on how reliable the concept of equinox is and if it still deserves to be preserved in cultural
astronomy studies, including archaeoastronomy and ethnoastronomy.
2 Discussion: Which Equinox?
Until recent times, the megalithic monuments in Europe were the archaeological
remains earning all the credit for any potential astronomical knowledge of the earliest ancestors of humankind. However, a discovery in southeast Anatolia has changed
these ideas. There, on a barren isolated hill called Göbekli Tepe, a team of German
and Turkish archaeologists (see Schmidt, 2006 for the discovery) have been
excavating a cluster of suggestive cyclopean monuments erected with large, megaJ. A. Belmonte