  Observation of auroras at low latitudes is an extremely rare event typically
associated with major magnetic storms due to intense Earth-directed Coronal
Mass Ejections. Since these energetic events represent one of the most
important components of space weather their study is of paramount importance to
understand the Sun-Earth connection. Due to the rarity of these events, being
able to access all available information for the few cases studied is equally
important. Especially if we refer to historical periods in which current
accurate observations from ground-based instruments or from space were not
available. Certainly, among these events we must include the great aurora of
February 4, 1872. An event whose effects have been observed in different
regions of the Earth. What we could consider today a global event, especially
for its effects on the communication systems of the time, such as the
transatlantic cable that allowed a connection between the United States and
Europe since 1866. In this paper we describe the main results of the
observations and studies carried out by Angelo Secchi at the Observatory of the
Roman College and described in his "Memoria sull'Aurora Elettrica del 4
Febbraio 1872" for the Notes of the Pontifical Academy of new Lincei. This note
is extremely modern both in its multi-instrumental approach to the study of
these phenomena and in its association between solar-terrestrial connection and
technological infrastructures on the Earth. The Secchi's note definitely
represents the first example of analysis and study of an event on a global
scale, such as the Atlantic cable, affecting the Earth. What we nowadays call
an extreme space weather event.
