可见光及X射线波段的猫眼星云
影像来源与版权:NASA, ESA, Hubble Legacy Archive; Chandra X-ray Obs.; Processing & Copyright: Rudy Pohl

说明:有人说,它看来像只猫眼,不过也有人说,它或许像个庞大的海螺壳。它其实是一颗类太阳恒星,在生命末期抛出的气体所织成的,也是现知最明亮结构最清晰的行星状星云之一。这团星云滨死的中心星,或许在一系列规律的脉动里,抛出了外层气壳,形成星云外围的同心壳层结构。然而,美丽复杂但对称的美丽内围结构到底是如何形成的,目前的了解仍不完整。这幅主题影像组合了经过数位锐化的哈伯太空望远镜影像,与及钱卓拉天文卫星拍摄的X射线影像。这座漂浮在太空中的精美雕塑,宽约半光年。借由望进这只猫眼,人类也预见了我们太阳的宿命,有一天它会演化到行星状星云阶段… 只不过这得再过50亿年左右。
翻译:“每日一天文图”成大物理分站

The Cat’s Eye Nebula in Optical and X-ray
Image Credit & Copyright: NASA, ESA, Hubble Legacy Archive; Chandra X-ray Obs.;
Processing & Copyright: Rudy Pohl

Explanation: To some it looks like a cat’s eye. To others, perhaps like a giant cosmic conch shell. It is actually one of brightest and most highly detailed planetary nebula known, composed of gas expelled in the brief yet glorious phase near the end of life of a Sun-like star. This nebula’s dying central star may have produced the outer circular concentric shells by shrugging off outer layers in a series of regular convulsions. The formation of the beautiful, complex-yet-symmetric inner structures, however, is not well understood. The featured image is a composite of a digitally sharpened Hubble Space Telescope image with X-ray light captured by the orbiting Chandra Observatory. The exquisite floating space statue spans over half a light-year across. Of course, gazing into this Cat’s Eye, humanity may well be seeing the fate of our sun, destined to enter its own planetary nebula phase of evolution … in about 5 billion years.
Astronomy Picture of the Day 05/01/2019