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Chromospheric Ca II and Mg II emission in two high latitude supergiant stars (HR 4912 and HD 161796) demonstrates the presence of chromospheres in evolved metal deficient populations. Spectroscopic evidence for circumstellar material around these stars suggests they have lost mass and belong to a much older population of low-mass stars evolving off the tip of the asymptotic giant branch toward the...
On May 22, 1989 the Japanese Ginga Team discovered a new X-ray source that was cataloged as GS 2023+338. This source was subsequently identified as coincident in position with a previously known nova cataloged as V404 Cygni. Its last recorded outburst was in 1938 when it rose to about 12th mag. Spectroscopic data were obtained and confirmed the nature of the outburst. Additional ground based data...