堰蜓座的暗星云

2024年7月22日

Chamaeleon Dark Nebulas
Image Credit & Copyright: Chang Lee

Explanation: Sometimes the dark dust of interstellar space has an angular elegance. Such is the case toward the far-south constellation of Chamaeleon. Normally too faint to see, dark dust is best known for blocking visible light from stars and galaxies behind it. In this 36.6-hour exposure, however, the dust is seen mostly in light of its own, with its strong red and near-infrared colors creating a brown hue. Contrastingly blue, the bright star Beta Chamaeleontis is visible on the upper right, with the dust that surrounds it preferentially reflecting blue light from its primarily blue-white color. All of the pictured stars and dust occur in our own Milky Way Galaxy with one notable exception: the white spot just below Beta Chamaeleontis is the galaxy IC 3104 which lies far in the distance. Interstellar dust is mostly created in the cool atmospheres of giant stars and dispersed into space by stellar light, stellar winds, and stellar explosions such as supernovas.

Tomorrow’s picture: Chandra Crab (25)

堰蜓座的暗星云
影像提供与版权: Chang Lee

说明: 有时候，星际空间带棱有角的暗星云也可以很优美。位于南天极区的堰蜓座即为例证之一。极为昏暗通常不得见的黝黑尘埃，很能遮挡后方的恒星和星系之可见光。不过，在这幅36.6小时长曝光影像里，这些尘埃所反射的是自身发出的光，而其强烈的红光和近红外光辐射，则让它们带着棕色的色泽。影像中右方对比鲜明泛蓝亮区，源自亮星小斗一周围的尘埃，高效率的反射这颗蓝白恒星所发出的蓝光所致。这片视野里的恒星和尘埃，几乎全在我们的银河系之内，唯一例外是小斗一下方的白斑为座落在遥远后方的星系IC 3104。星际尘埃大多形成于巨星的低温大气里，然后在星光、恒星风、和诸如超新星这类恒星爆炸的推送下，散布到宇宙空间里。 （Chamaeleon 堰蜓座；Beta Chamaeleontis 小斗一）

明日的图片: Chandra Crab (25)