Century-scale persistence in longitude distribution in the Sun and in silico

¹ Tartu Observatory, 61602 Tõravere, Estonia e-mail: pelt@aai.ee
² Astronomy Division, Department of Physical Sciences, PO Box 3000, 90014 University of Oulu, Finland
³ Manchester Computing, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
⁴ Department of Mathematics, University of Manchester, Oxford Road, Manchester, M13 9PL, UK

Received: 26 May 2004
Accepted: 22 October 2004

Abstract

Using Greenwich sunspot data for 120 years it was recently observed that activity regions on the Sun's surface tend to lie along smoothly changing longitude strips 180°  apart from each other. However, numerical experiments with random input data show that most, if not all, of the observed longitude discrimination can be an artifact of the analysis method.