Introduction

The astronomical interpretation of stone circles and standing stones has a long history; in the late seventeenth century, for example, Martin Martin, writing about the Ring of Brodgar and the Stones of Stenness in Orkney, records that ‘Several of the Inhabitants have a Tradition that the Sun was worshipped in the larger, and the Moon in the lesser Circle’ (1716, 365). In recent years a scientific basis for interpretation of the archaeological evidence in astronomical terms has been proposed by Alexander Thom (Thom, A. 1967; 1971; Thom & Thom 1978). In 1965 he began his introduction to megalithic astronomy: ‘Much has been written for and against the astronomical significance of the stone circles, stone alignments, etc., which are scattered throughout these islands and indeed much further afield. There is, however, universal agreement that the erectors, herein called for convenience Megalithic man, marked the rising and setting points of the solsticial Sun’ (Thom, A. 1965, 1).