Light curves for GT Muscae. The upper panel (adapted from Murdochet al.[1]) shows the long-term variability after a model of the eclipsing binary variability has been removed. The orbital period of HD 101379 is shown in red. The lower panel showsTESS data,[2] in which the eclipses (both primary and secondary) are clearly visible. The orbital period of HD 101380 is shown in red.
In 1929,Willem van den Bos discovered that GT Muscae is a visualdouble star, whose A (HD 101379) and B (HD 101380) components were separated by 0.2arc seconds at the time he observed it.[9] Examiningphotographic plates in 1964, Wolfgang Strohmeieret al. discovered that GT Muscae is a variable star.[11] In 1979, based onspectroscopic features, Edward Weiler and Robert Stencel listed GT Muscae as a likely RS CVn variable.[12] Eclipses of the HD 101380 pair were first reported byAndrew Collier Cameron in his 1982 PhD thesis, in which he also determined that pair's orbital period.[13] The entire star system was given thevariable star designation GT Muscae in 1988.[14]
Strong, variable, 5 GHz radio emission from GT Muscae, indicative offlares, was detected in 1982 and was interpreted as indicating high levels ofchromospheric andcoronal activity.[15]
GT Muscae was detected in the early observations of theUhuru X-ray satellite, originally denoted as 2U 1134–161, later renamed 4U 1137–65.[16][17] Michael Garciaet al. identified HD 101379 as the source seen byUhuru, in 1980.[18] During the 2010-2019 decade, GT Muscae showed the most X-ray flare activity of any star in the sky, producing flares with energies as high as ~1038ergs.[10]
^Kallinger, T.; Beck, P. G.; Hekker, S.; Huber, D.; Kuschnig, R.; Rockenbauer, M.; Winter, P. M.; Weiss, W. W.; Handler, G.; Moffat, A. F. J.; Pigulski, A.; Popowicz, A.; Wade, G. A.; Zwintz, K. (2019-04-01). "Stellar masses from granulation and oscillations of 23 bright red giants observed by BRITE-Constellation".Astronomy & Astrophysics.624: A35.arXiv:1902.07531.Bibcode:2019A&A...624A..35K.doi:10.1051/0004-6361/201834514.ISSN0004-6361.
