AURORAE ΑND ARCHAEOMAGNETISM FROM THE 1st MILLENNIUM B.C. CHINA, GREECE AND ITALY: A BRIEF OVERVIEW AND CRITICAL ASSESSMENT

Abstract

Auroral reports from ancient Chinese records and from Greece and Italy, from historical sources (Bamboo

Annals, Tai ping yu lan, Ch'unch'iu period and Aristotle, Anaxagoras, Seneca, Pliny, Livy, respectively) in the

1 st millennium B.C., are discussed in relation to the geomagnetic pole (GP) coordinates through archaeo

magnetic inclination and declination data. It is shown that the expected auroral oval with its extension to a

maximum of radius 30o around the GP occasionally reaches the Chinese / Southern Mediterranean mid lati

tudes and eastern longitudes: for China 35ο-40 ο and 95ο-125 ο respectively, and for Greece/Central Italy, 35ο-

40ο and 10ο-25ο respectively; two distant regions where two great cultures flourished. Of the nine Chinese

records those of 1000-900 B.C., 687 B.C., 193 B.C., 139 B.C., 32 B.C., 30 B.C. and 15 B.C. records are justified by

a mid latitude geomagnetic pole which gives certain mid latitude aurorae. For the 166 B.C. and 154 B.C.

available archaeomagnetic data the position of the VGP does not justify observation of aurorae. Archaeo

magnetic data for Chinese accounts derived from South Korea, Japan and England reduced to mid China

location are also used to determine GP at a reduced site of common latitude in China, but due attention and

discussion of non-dipole magnetic sources and their calculated drift rates is made, to explain the unattaina

ble observation of aurorae at central Chinese latitudes. Similarly, in southern Eastern Mediterranean area

(Greece, Italy) 33 data are used and most are commensurable with the inclined GP towards mid latitudes,

included within the auroral oval or at its southern maximum extension taking into account associated errors.

Highly acceptable aurorae accounts and problematic ones are explained in terms of smooth or rapid, respec

tively, changes in the magnetic inclination and declination positions, reinforced by large age errors. Virtual

Geomagnetic poles (VGP) for examined regions are ranging between 51o to 71o for latitude and between 1 o to

123o for longitude for auroral observation dates of the 1st millennium B.C. to 1st century A.D.