Equations are not being displayed properly on some articles. We hope to have this fixed soon. Our apologies.

Sparavigna, A. (2016). The Decumani of Naples and the Minor Lunar Standstill. PHILICA.COM Article number 608.

ISSN 1751-3030  
Log in  
  1271 Articles and Observations available | Content last updated 16 December, 19:01  
Philica entries accessed 3 493 736 times  

NEWS: The SOAP Project, in collaboration with CERN, are conducting a survey on open-access publishing. Please take a moment to give them your views

Submit an Article or Observation

We aim to suit all browsers, but recommend Firefox particularly:

The Decumani of Naples and the Minor Lunar Standstill

Amelia Carolina Sparavignaunconfirmed user (Department of Applied Science and Technology, Politecnico di Torino)

Published in enviro.philica.com


Article body

The Decumani of Naples and the Minor Lunar Standstill


Amelia Carolina Sparavigna

Politecnico di Torino


Abstract: Here we are proposing an astronomical analysis of the direction of the Decumani of Naples, made by means of a modern ephemeris, the Photographer's Ephemeris, a well-known software used for planning outdoor photography. The old part of Naples had a layout based on a chessboard of parallel and perpendicular streets, the Decumani and Kardines, where the Decumani have an alignment with moonrise and moonset azimuths on minor lunar standstills. Such reference to the moon in the alignment of the streets is also found for Torino.

Keywords: Archaeoastronomy, Satellite Images, Architecture, Modern Ephemerides


Introduction: In his fundamental book on the ancient town planning [1], Francis John Haverfield (1860–1919), a British historian and archaeologist, has discussed several Italian settlements, starting from the very old examples of Terramare people arriving to the towns of Roman Empire. Of the empire, we have a huge mass made of "certain facts, both in Italy and in the provinces" for studying the town planning. One of the planning we find analyzed in his book is that of Naples, and it is from Haverfield’s words that we start for showing a possible astronomical orientation of the Decumani of Naples. Using the Photographer's Ephemeris, we will see an interesting alignment of these decumani to moonrise/moonset on minor lunar standstills. Such alignments had been observed for Torino too [2,3].

Naples: As told in [1], Naples, the Greek and Roman Neapolis, was a Greek city, "the most prosperous of the Greek towns in Campania". After 90 BC it becomes a Roman 'municipium', but retaining much of its Greek civilization. "A writer of the early first century after Christ, Strabo, states that abundant traces of Greek life survived there … Even later Tacitus calls it a 'Greek city', and Greek was still used for official inscriptions there in the third century". Then Haverfield is noting than "Neapolis town had, as certain existing streets declare, a peculiar form of town-planning. The area covered by these streets is an irregular space of 250 acres in the heart of the modern city, about 850 yds from north to south and 1,000 yds from east to west. In Roman days three straight streets ran parallel from east to west and a large number of smaller streets, twenty or so, ran at right angles to them from north to south" [1]. The Figure 1 is showing the Ancient Naples in the map given in [1].


 Figure 1: The Ancient Naples and the three Decumani [1].


Haverfield continues observing that the quite oblong insulae are suggesting the following fact. Since Naples had origin as a Greek city, "these narrow oblongs have been supposed to represent a Greek arrangement. They do not, however, correspond to anything that is known in the Greek lands, either of the Macedonian or of any earlier period. The conclusion is difficult to avoid that this Greek city of Naples adopted an Italian street-scheme, but laid it out with more scientific regularity than the early Italians themselves. When this occurred and why, is wholly unknown. That the result is not an unpractical form of building is shown by the fact that similar long and narrow house-blocks are a characteristic feature of modern Liverpool, though they seldom occur in other English towns, unless intermixed with square and other blocks" [1].

It is very interesting the Haverfield's observation: the planning of the town is reflecting an Italic scheme, rather than a Greek one.

Decumani of Naples and the Moon: The Roman settlements were continuing an Italic tradition then. They were arranged in insulae created by a chessboard of parallel and perpendicular streets, known as decumani and kardines. This layout was based on the Roman surveying method of Centuriation [4]. In general, the decumani are aligned along the apparent motion of the sun from rising to setting, and the kardines along the direction of the "axis mundi", the axis due north about which the sky is rotating. In fact, in the book of Haverfield, it is told that the Decumanus could have been oriented to the rising sun on the day of the foundation of the town [4,5], and then, in previous papers, we have discussed the orientation of some towns and settlements according to an astronomical orientation based on the sun (see for instance [6,7]). However, as recently discussed, some towns are showing in their planning some alignments to moonrise and moonset on lunar major and minor standstill [2,3,8-10]. To see them, we can use a simple mathematical formula, but they are more evident with a software showing them on the satellite maps of today modern towns. This is what we preferred for the case of Torino and other Roman towns in Piemonte (Torino has the Decumanus, today Via Garibaldi, aligned along moonrise and moonset on lunar minor standstills).

Wikipedia tells us that on October 2015 we had a minor lunar standstill and that on April 2025, there will be a major lunar standstill. Let us consider Naples and the minor lunar standstill: in the images of Figure 2 we can see the Decumani and the directions of moonrise and moonset azimuths. The alignment is remarkable; possibly, it was planned according to an augur discipline of good omens for the town, linked to the moon. If it were so, it means that, besides the apparent motion of the sun, also that of the moon was important, not only for northern traditions but also for Greeks and Romans.





Figure 2: The blue lines represent the moonrise and moonset azimuths on a minor lunar standstill. Note that the direction of the Decumani is along the moonrise azimuth (3 October 2015) and to the moonset azimuth (18 October 2015) on the minor lunar standstill of 2015. The yellow and orange lines are the sunrise and sunset azimuths. The images had been obtained from snapshots of the Photographer’s Ephemeris results.



[1]  Haverfield, F. (1913), Ancient Town-Planning, Oxford, Clarendon.

[2] Sparavigna, A. C. (2016). The Orientation of a Street of Turin along the Major Southern Moonrise Direction. SSRN Journal. DOI: 10.2139/ssrn.2779906

[3] Sparavigna, A. C. (2016). Torino e i lunistizi. PHILICA.COM Article number 603.

[4] Sparavigna, A. C. (2015). Roman Centuriation in Satellite Images. PHILICA Article number 547. Available at SSRN: http://ssrn.com/abstract=2742223

[5] Barthel, W. (1911). Römische Limitation in der Provinz Africa, 1911, Carl Georgi Verlag, Bonn.

[6]  Sparavigna, A. C. (2016). Roman Towns Oriented to Sunrise and Sunset on Solstices. SSRN Journal. DOI: 10.2139/ssrn.2777118

[7] Sparavigna, A. C. (2012). The orientation of Trajan's town of Timgad. arXiv preprint arXiv:1208.0454.

[8] Sparavigna, A. C. (2016). Alcuni siti romani in Piemonte orientati coi lunistizi. PHILICA.COM Article number 604.

[9] Sparavigna, A. C. (2016). Some Notes on the Urban Planning of Mediolanum and on the Orientation of Its Decumanus. SSRN Journal. DOI: 10.2139/ssrn.2779265

[10]  Frison, C. & Ottavi, A. M. (2008). L'Osservazione del Lunistizio nella Milano Celtica, available at http://www.carlofrison.it/milano-lunistizi.html




Information about this Article
This Article has not yet been peer-reviewed
This Article was published on 29th May, 2016 at 10:45:38 and has been viewed 1179 times.

Creative Commons License
This work is licensed under a Creative Commons Attribution 2.5 License.
The full citation for this Article is:
Sparavigna, A. (2016). The Decumani of Naples and the Minor Lunar Standstill. PHILICA.COM Article number 608.

<< Go back Review this ArticlePrinter-friendlyReport this Article

Website copyright © 2006-07 Philica; authors retain the rights to their work under this Creative Commons License and reviews are copyleft under the GNU free documentation license.
Using this site indicates acceptance of our Terms and Conditions.

This page was generated in 0.2912 seconds.