Astronomy Picture of the Day——相机镜头下的猎户座
Discover the cosmos! Each day a differentimage or photograph of our fascinating universe is featured, along with a briefexplanation written by a professional astronomer.
Camera Orion
Image Credit & Copyright: Derrick Lim
Explanation: Do you recognize thisconstellation? Although it is one of the most recognizable star groupings onthe sky, Orion's icons don't look quite as colorful to the eye as they do to acamera. In this 20-image digitally-composed mosaic, cool red giant Betelgeusetakes on a strong orange tint as the brightest star at the upper left. Orion'shot blue stars are numerous, with supergiant Rigel balancing Betelgeuse at thelower right, and Bellatrix at the upper right Lined up in Orion's belt arethree stars all about 1,500 light-years away, born from the constellation'swell-studied interstellar clouds. Below Orion's belt a reddish and fuzzy patchthat might also look familiar -- the stellar nursery known as Orion's Nebula.Finally, just barely visible to the unaided eye but quite striking here bycamera is Barnard's Loop -- a huge gaseous emission nebula surrounding Orion'sBelt and Nebula discovered over 100 years ago by the pioneering Orionphotographer E. E. Barnard.
相机镜头下的猎户座
说明：你认出这个星座了么? 虽然它是天空中最容易辨认的星群之一，但肉眼看到的猎户座恒星并不是我们从相机里看到的那样色彩鲜明。在这张由20幅图像数字合成的拼接影像中，左上角呈现出橙色的明亮恒星是低温的红巨星参宿四。猎户座拥有数量众多的高温蓝色恒星，其中位于右下角、与参宿四（左上角的）遥相呼应的是红超巨星参宿七，而右上角的参宿五与构成猎户腰带的三颗恒星，与地球的距离都有约1500光年，它们都诞生于猎户座内那片天文学家熟知的星际云。猎户腰带下面的一个红色模糊斑点似乎有些熟悉——它就是被称为恒星育儿所的猎户星云，许多恒星由此诞生。最后是肉眼几乎不可见但在相机内却非常醒目的巴纳德环，它是一个围绕猎户腰带和猎户星云的庞大气体发射星云，天文学家E.E巴纳德在100多年前首先发现了它。
近期文章：
Astronomy Picture of the Day——M104：草帽星系