金牛座EQ

金牛座EQ是黃道星座金牛座的一顆三合星，它包括密接的食雙星。該系統過於黯淡，無法用肉眼觀察，基線的視星等為10.5等。在食的期間，系統的主極小期亮度降至11.03等，然後在次極小期降至10.97等。次極小期是全食。根據視差的量測，它位於距離太陽約730光年的地方。 恆星HV 6189在1940年被哈羅·沙普利（ Harlow Shapley）和艾米莉·M·休斯（英语：Emily M. Hughes）（ Emily M. Hughes）確認為短週期變星，然後再1954年，蘇聯天文學家弗拉基米爾·普拉托諾維奇·采謝維奇（英语：Vladimir Platonovich Tsesevich）對其進行了更深入的研究。它被確定為大熊座W型變星，並被注意到位於疏散星團昴宿星團的區域。對采謝維奇數據的分析以及B.S.Whitney（英语：Balfour S.Whitney）在1972年的後續觀測表明，它的週期是可變的。他在孔科利天文臺（英语：Konkoly Observatory）的觀測顯示週期為8.19 h。Wystan Benbow（英语：Wystan Benbow）和Robert L.Mutel（英语：Robert L.Mutel）在1995年建立了食變星的光變曲線，顯示了恆星表面存在活動區的證據。軌道週期的變化繼續被觀察到，在2002年Theodor Pribulla（英语：Theodor Pribulla）和Martin Vańko（英语：Martin Vańko）提出它是由系統中的第三個天體引起的。他們將其建模為低質量的紅矮星，軌道週期為50.2年。 這是一個淺接觸的聯星系統，屬於大熊座W型變星的A子型。它的軌道週期為8.1924小時，半長軸是太陽半徑的2.48倍。軌道呈現週期性變化，其週期為22.7年，振幅為0.0058天。2010年觀測到類似凌的事件。質量更大的成分是一顆有很深對流層的太陽型恒星，出現磁活動，覆蓋著顯著的星斑 。 ASAS-SN Variable Stars Database. ASAS-SN Variable Stars Database. ASAS-SN. [6 January 2022]. （原始内容存档于2023-01-11）.  Brown, A. G. A.; et al. 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