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The legendary Rome halo displays.

Walter Tape¹, Eva Seidenfaden, Gunther P Können

¹University of Alaska, Department of Mathematics 6660, Fairbanks , Alaska 99775-6660, USA. ffwrt@uaf.edu

|November 28, 2008

Summary

Historical halo displays in Rome from 1629 and 1630 are re-examined. Documentation is insufficient to confirm rare halo phenomena like the 28-degree halo, though the displays remain significant for early atmospheric optics science.

Area of Science:

Atmospheric optics
Historical meteorology
Optical phenomena

Background:

The 1629 and 1630 Rome halo displays are historically significant in early halo research.
The 1629 display is often cited for a purported 28-degree circular halo.

Purpose of the Study:

To critically evaluate the documentation of the 1629 and 1630 Rome halo displays.
To ascertain the validity of reported rare halo phenomena, specifically the 28-degree halo.

Main Methods:

Analysis of seventeenth-century correspondence and publications.
Historical document review and interpretation.

Main Results:

The available documentation for both halo displays is found to be weak.

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Little evidence supports the existence of a 28-degree halo or other rare halos during these displays.

Conclusions:

The interpretations of the 1629 and 1630 Rome halo displays are not definitively supported by existing historical records.
Despite weak documentation, these displays were pivotal in the inception of modern halo science.