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Three Long Period Variables in Sagittarius

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Barbara Hatfield

Maria Mitchell Observatory, Nantucket, Massachusetts

Abstract

Several variables in VSF 193 in Sagittarius were studied during the suumer of 1972, three of which were of Mira type.

Variable B28* (18h 22m 55s, -22¡ 50.9', 1900) was discovered to have varying amplitude, ranging from magnitude 13.3 to 13.7 for its low and high maxima, to magnitude 15 at minima, with a period of 249 days.

The second star, B29* ( 18h 27m 17s, -20¡ 10.4', 1900) was discovered by Pamela Bonnell in 1971 on the Nantucket plates. The star varies from magnitude 11.6 to below 14.2. It appears to have a changing period. From about JD 18,000 to 33,000 a period of 345 days fits the data. From about 35,000 to the present the period appears to be 358 days. Whether this change is a single event or is part of a systematically varying period remains to be determined.

The third star B30* (18h 24m 35s, -28¡ 07.0', 1900) also has a changing period. d