The Grand Aurorae Borealis Seen in Colombia in 1859

TL;DR

This paper documents a rare low-latitude observation of aurora borealis in Colombia during the 1859 Carrington Event, supported by historical reports and analysis of geomagnetic conditions.

Contribution

It provides one of the most detailed historical accounts of aurora sightings at low latitudes during a major geomagnetic storm, linking it to the exceptionally low geomagnetic pole position.

Findings

Aurora observed in Colombia at 8.75° N during 1859 event

Geomagnetic pole was at its lowest in over 500 years

Historical reports align with geomagnetic data indicating intense solar activity

Abstract

On Thursday, September 1, 1859, the British astronomer Richard Carrington, for the first time ever, observes a spectacular gleam of visible light on the surface of the solar disk, the photosphere. The Carrington Event, as it is nowadays known by scientists, occurred because of the high solar activity that had visible consequences on Earth, in particular reports of outstanding aurorae activity that amazed thousands of people in the western hemisphere during the dawn of September 2. The geomagnetic storm, generated by the solar-terrestrial event, had such a magnitude that the auroral oval expanded towards the equator, allowing low latitudes, like Panama's 9$^\circ$ N, to catch a sight of the aurorae. An expedition was carried out to review several historical reports and books from the northern cities of Colombia, allowing the identification of a narrative from Monter\'ia, Colombia (8$^\circ$ 45' N), that describes phenomena resembling those of an aurorae borealis, such as fire-like lights, blazing and dazzling glares, and the appearance of an immense S-like shape in the sky. The very low latitude of the geomagnetic north pole in 1859, the lowest value in over half a millennia, is proposed to have allowed the observations of auroral events at locations closer to the equator, and supports the historical description found in Colombia. The finding of such chronicle represents one of the most complete descriptions of low-latitude sightings of aurorae caused by the Carrington Event.