Astronomy Picture of the Day——御夫座AE星与火焰星星云
Discover the cosmos! Each day a differentimage or photograph of our fascinating universe is featured, along with a briefexplanation written by a professional astronomer.
AE Aurigae and the Flaming Star Nebula
Image Credit & Copyright: Amir Abolfath(TWAN)
Explanation: Is star AE Aurigae on fire?No. Even though AE Aurigae is named the flaming star, the surrounding nebula IC405 is named the Flaming Star Nebula, and the region shape gives the appearanceof fire, there is no fire. Fire, typically defined as the rapid molecularacquisition of oxygen, happens only when sufficient oxygen is present and isnot important in such high-energy, low-oxygen environments such as stars. Thematerial that appears as smoke is mostly interstellar hydrogen, but doescontain smoke-like dark filaments of carbon-rich dust grains. The bright starAE Aurigae, visible just to the lower right of the image center, is so hot itglows blue, emitting light so energetic it knocks electrons away fromsurrounding gas. When a proton recaptures an electron, light is emitted, asseen in the surrounding emission nebula. Featured here, the Flaming Star nebulalies about 1,500 light years distant, spans about 5 light years, and is visiblewith a small telescope toward the constellation of the Charioteer (Auriga).
御夫座AE星与火焰星星云
说明：
御夫座AE星是着火了吗？其实并没有。
尽管御夫座AE星被称作火焰星，其附近的星云IC 405的命名是火焰星云，因为该区域的外形呈现出火焰形状，但其实它并没有着火。
火焰通常被定义为物质与氧气发生化学反应的产物，只有在拥有足够氧气时才能发生，因此在高能低氧的环境中（例如恒星），火焰并不存在。这种烟雾状的物质其实主要是星际空间的氢，有些是富含碳的黑暗丝状尘埃颗粒。
亮星御夫座AE星在图像中心右下方可见，它非常炽热，散发出蓝色的辉光，它发出的高能星光将电子从周围气体中撞出。当质子重新获得电子时，恒星就会发光，就像在附近的发射星云中看到的那样。在这幅特征图像中，火焰星云距离我们约1,500光年，跨度有5光年，我们用一台小型望远镜望向御夫座方向就能够看到它。
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