Page:Madras journal of literature and science 3rd series 1, July 1864.djvu/108

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96
Discovery of two new variable Stars.

brilliancy on the 20th. Full moonlight prevented any further records of the vanishing star, but taking advantage of a very fine interval during the totality of the lunar eclipse of June 1st, its invisibility was satisfactorily established; and though sought for on every suitable opportunity throughout the following five months, it has not since re-appeared.

The light comparisons actually made were as follows:

1863 May 20th . . . . . . . . . . . . 9·1 magnitude.
1863 May 21st . . . . . . . . . . . . 9·6 magnitude.
1863 May 22nd . . . . . . . . . . . . 10·1 magnitude.
1863 May 24th . . . . . . . . . . . . 10·5 magnitude.
1863 May 25th . . . . . . . . . . . . 11·0 magnitude.
1863 May 28th . . . . . . . . . . . . 11·4 magnitude.
1863 May 27th . . . . . . . . . . . . 11·9 magnitude.
1863 May 28th . . . . . . . . . . . . 12·2 magnitude.

Of the other new variable, situated in the constellation Sagittarius, little more can be said than that it was first seen on July 19th 1883, as a somewhat ruddy star of the 8½ magnitude; and that from then until the present time it has slowly and steadily diminished to the 12th magnitude, or one twenty-fifth of its greatest recorded intensity of light. Dates of its actual invisibility in previous years cannot be furnished as in the case of U Scorpii, but if visible at all it was most certainly less than 11½ magnitude on August 30th 1859; on July 22nd, and on August 7th 1860.

The approximate positions of the two new stars, reduced to 1860, are:

Light Range. Right Ascension. South Declination.
h. m. s. °
U. Scorpii 9·5 to below 13·5 magnitude 16 14 25·5 17 33 21
T Sagittarii. 8·5 to below 12·0 magnitude 19 8 9·4 17 12 11
N. R. Pogson.

Madras Observatory,
December 1863.