Our Astronomical Column

Abstract

ANCIENT OCCULTATIONS OF ALDEBARAN.—In NATURE, vol. xxxi. p. 182, reference was made to an occultation of Aldebaran which Bullialdus found recorded in a Greek manuscript, and which it had been supposed was observed at Athens on March 11, A. D. 509. The extract from the manuscript is given at p. 172 of the well-known work of Bullialdus, “Astronomia Philolaica.” The observation is perhaps mentioned in somewhat undecided terms, inasmuch as it is rather implied that after twilight had ended the moon seemed to have occulted the star; nevertheless we have its position described as close to the moon at the time of observation; and further: “Stella quippe apposita erat parti, per quam bisecatur limbus Lunæ illuminatus.” If we remember rightly, Street, amongst others, has pointed out that the occultation itself could not have been seen at Athens, but must have been observed at some more eastern station. The following are results of a recent computation in which the moon's place has been determined on the same elements which closely represent the occultations observed in China B.C. 69, February 14, and A.D. 361, March 20, referring to the planets Mars and Venus respectively, as well as other phenomena recorded previous to the fourth century.