金牛座埃普西隆星：有行星的恆星
Epsilon Tauri: Star with Planet
來源：Reg Pratt｜發表日期：2024-01-26
金牛座伊普西隆位於 146 光年之外。它是一顆 K 型紅巨星，溫度比太陽低，但半徑約為太陽的 13 倍，光度幾乎是太陽的 100 倍。這顆巨星是金牛座疏散星團的一員，它的專有名稱是艾因，與更亮的巨星奧爾德巴蘭一起構成了金牛座的眼睛。在金牛座塵土飛揚的烏雲環繞下，人們還知道epsilon Tau 有一顆行星。它是一顆比木星還大的氣體巨行星，軌道週期為 1 . 6 年。雖然不能直接看到這顆系外行星，但在漆黑的夜晚，它的母星金牛座epsilon 星很容易被肉眼看到。
原文：silon Tauri lies 146 light-years away. A K-type red giant star, epsilon Tau is cooler than the Sun, but with about 13 times the solar radius it has nearly 100 times the solar luminosity. A member of the Hyades open star cluster the giant star is known by the proper name Ain, and along with brighter giant star Aldebaran, forms the eyes of Taurus the Bull. Surrounded by dusty, dark clouds in Taurus, epsilon Tau is also known to have a planet. Discovered by radial velocity measurements in 2006, Epsilon Tauri b is a gas giant planet larger than Jupiter with an orbital period of 1.6 years. And though the exoplanet can't be seen directly, on a dark night its parent star epsilon Tauri is easily visible to the unaided eye.
※ 本文由萌芽機器人自動轉貼自每日一天文圖（Astronomy Picture of the Day，APOD），原文為英文，正體中文是透過 DeepL 翻譯及 OpenCC 進行自動處理，內容僅供參考，若有任何錯誤之處還請見諒！
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