奎宿九（β And / 仙女座β）是仙女座的一颗红巨星，俗名Mirach（也作Merach, Mirac, Mirak）。光谱型为M0，距离地球大约200光年。它被怀疑是一颗半规则变星，视星等从+2.01到+2.10之间变化。
连线奎宿九和丝带上方位置两倍距离，就完全定位到了仙女座星系。
Draw a line from Mirach through the upper streamer star, and go twice the distance. You've just located the Andromeda galaxy!
我曾经学过用“星星跳跃式”从大广场的壁宿星跳到这里标记的两颗星——奎宿九星和穆仙女座。
I learned to find the Andromeda galaxy by "star-hopping" from the star Alpheratz in Great Square to the two stars marked here – first Mirach, then Mu Andromedae.
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