2014 programme

Auxiliary Southern Double Star Catalogues

Andrew James

Non-Affiliated Independent Amateur Astronomer (NAIAA)

Since the early 19th Century, southern observers have created only a dozen or so prominent southern double stars catalogues. Likely the most important of these were the large number of discovered pairs made by J. Dunlop (DUN), J. Herschel (HJ), then later H.C. Russell (R) and R.T.A. Innes (I). These have all been reasonably well historically discussed elsewhere. Yet, there are many other smaller double star catalogues of which we continue to know little about. Most of these were extracted from either dedicated star sky surveys or were found by random happenstance while looking at other celestial objects or in measuring preexisting double stars.

This talk will specifically highlight the Captain W.S. Jacob (Jc) pairs found from Madras Observatory in India in 1850s, the Melbourne Double Star Catalogue (MLO) produced by Robert L.J. Ellery during the 1860s and 1870s, followed by the shorter catalogues of the Sydney Observatory observers, L. Hargrave (HRG), R.P. Sellors (SLR), and J.A. Pollock (POL) during the 1890s. A specific case will be the ninety-six listed Melbourne pairs, which has involved considerable time by the presenter in reconstructing the original data, not helped as this catalogue in its first outline now seems to be lost or no longer exists.

The talk will also discuss some of the most interesting examples of these pairs, which the presenter have been researching for a number of years. Most are probably more notable for the many oddities that these catalogues contain, and I will attempt to explain the reasoning behind listing them and the current real problems in finding some of the missing pairs. Also stated in particular detail is why earlier observers had missed some of the important and obvious bright double stars.