Andrew Cooper
Feb 20, 2020    Waikoloa, HI (map)
20cm f/6 Newtonian, Cave Astrola @ 61x
Seeing: 7 Transparency: 6 Moon: 0%

Ivory, no companion noted, triangle with ρHya and 10Hya

Captain William Henry Smyth
Feb 10, 1837    No. 6 The Crescent, Bedford, England (map)
150mm f/17.6 refractor by Tully 1827

A secondary Greenwich star, double, and the middle one in the head of Hydra. A 4, pale yellow; B 8½, purple. A long ray from Betelgeuze brought over Procyon, and carried nearly as far again, finds it about 14° south of the Præsepe; and nearly mid-way between Pollux and Cor Hydræ. This beautiful object was discovered by Σ., and is No. 1273 of the great Dorpat Catalogue, under these measures:

    Pos. 195° 34'  Dist. 3".21  Ep. 1830.60

But it must be remembered that Σ.'s measures did not arrive in this country till the autumn of 1837, though a catalogue of places, without angles or distance, had been nearly ten years in circulation. Mr. Dawes was therefore unacquainted with any other measures of this star, when his own observations indicated a change both in angle and distance, and this detection was creditable both to himself and his instrument. His whole series was as follows:

    Pos. 195° 16'  Dist. 4".34  Ep. 1831.13
         197° 36'        4".26      1832.20
         199° 10'        3".60      1834.00
   [WDS  311°            2".90      2020   ]

This accurate observer wished me to bestow some pains on the star, because he suspected it of rotation. "Indeed," he remarked, "were the small star visible fifty years ago, as it is now, it never could have escaped the scrutinizing eye of Sir W. Herschel." On this appeal, my observations, especially at the last epoch, were rigidly attended to, and the results corroborate the orbital motion. The distance seems decreasing, but this conclusion is not yet so evident as that of the angle, which, on weighing all the data, may have an annual progress of about +0°.8 per annum, or a circuit of 4½ centuries.

― A Cycle of Celestial Objects Vol II, The Bedford Catalogue, William Henry Smyth, 1844

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