金牛座EU

金牛座EU是在黃道星座金牛座的一顆變星。平均的視星等的亮度為8.07等，它太微弱了，因此肉眼看不到。基於視差的測量，到這顆恆星的距離約為3,900光年，但它正在以-2.5公里/秒的徑向速度漂移。這顆恆星在黃道附近的位置意味著它會發生月掩星的事件。 這顆恆星的變異性最早是由庫諾·霍夫邁斯特（英语：Cuno Hoffmeister）在1949年報導的，但後來他又報告說它沒有變異。由佛蘭克·布拉德肖·伍德（英语：Frank Bradshaw Wood）和同事於1963年根據阿扎爾諾娃（T. A. Azarnova）在1950-1951年的觀察，它最初被歸類為大熊座W型變星。愛德華·吉南（英语：Edward Guinan）在1966年對光電數據的分析表明，這是一顆造父型變星，其短的脈動週期約為2.105天。他在1972年將這一時期精確為2.1051+0.0004 −天。 1981年對這個和其它造父變星的光變曲線的研究表明，它屬於一個具有異常短時間和獨特行為的小群體。這表明金牛座EU可能是「第一個泛音」脈動星。1987年，Gieren和傑米·馬修斯（英语：Jaymie M. Matthews）提出這顆恆星可能有兩個脈動週期，但後來被駁斥了。 現在的證據主要支援恆星脈動處於「徑向第一泛音模式」的觀點。對於這類恆星來說，脈動週期中1%的半徑變化相對較小， 到2007年，分散在35年時間範圍內的觀測表明，這顆造父變星的脈動週期可能已經改變。 Brown, A. G. A.; et al. Gaia Early Data Release 3: Summary of the contents and survey properties. Astronomy & Astrophysics. 2021, 649: A1. Bibcode:2021A&A...649A...1G. S2CID 227254300. arXiv:2012.01533 . doi:10.1051/0004-6361/202039657 .  已忽略未知参数|collaboration= (帮助) (勘误: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR. 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