Alnilam is the middle and brightest of the three stars of Orion's Belt. It is the 29th-brightest star in the sky (the fourth brightest in Orion) and is a blue supergiant.

西方则称之为Alnilam，在佛兰斯蒂德命名法中则称为猎户座46，距离地球约1980光年（606秒差距）。 参宿二在猎户座中则名列第4位，是一颗B0Ia 蓝超巨星，也是已知最明亮的恒星之一。

參宿二 是全夜空第30亮的恆星，在獵戶座中則名列第4位，是一顆B0Ia 藍超巨星，也是已知最明亮的恆星之一。 從地球上觀測參宿二，會發現它位在獵戶座的腰帶上。

2020年1月30日 · Alnilam, also known as Epsilon Orionis or 46 Orionis, is the 4 th brightest star in the constellation of Orion, and the 29 th brightest star in the night sky. It is part of the famous Orion’s Belt asterism.

2024年12月11日 · Alnilam, Epsilon Orionis (ε Ori), is a bright blue supergiant star located approximately 1,180 light-years away in the constellation Orion. With an average apparent magnitude of 1.69, it is the fourth brightest star in Orion and the 29th brightest star in the sky.

Epsilon (ε) Orion, Alnilam, is a brilliant white star occupying the central position in Orion ‘s belt. Alnilam, Anilam, Ainilam, and Alnihan are from Al Nitham, or Al Nathm, the String of Pearls, or, as British physicist Robert Recorde (1500-1558) said, the Bullions set in the middle of Orion’s Belt.

The brightest of the Belt stars (which Bayer lettered in alphabetic order, again from right to left, Delta, Epsilon, and Zeta), and ranking fourth in the whole constellation, Alnilam shines at bright second magnitude (1.70).

2021年3月9日 · Alnilam is the middle star in the famous three-member belt of Orion, the Hunter. The belt is so easily recognizable because all three stars are spaced evenly in a (roughly) …

Alnilam, the blue supergiant star, has a variable brightness that ranks it as the 29th most luminousstar of all the known stars viewed from Earth. Its luminosity is the amount of energy emission from this giant star relative to the Sun.

Alnilam, also designated as ε Orionis (epsilon Orionis), is a variable and double hypergiant star of spectral class B0 in the constellation of Orion. Alnilam visual magnitude is 1.7, making it the 28th brightest star in the sky.