2025年1月8日
Supernova Remnants Big and Small
Image Credit & Copyright: Stéphane Vetter (Nuits sacrées)
Explanation: What happens after a star explodes? A huge fireball of hot gas shoots out in all directions. When this gas slams into the existing interstellar medium, it heats up so much it glows. Two different supernova remnants (SNRs) are visible in the featured image, taken at the Oukaïmeden Observatory in Morocco. The blue soccer ball-looking nebula toward the upper left is SNR G179.0+02.6, which appears to be the smaller one. This supernova, about 11,000 light years distant, detonated about 50,000 years ago. Although composed mostly of hydrogen gas, the blue light is emitted by a trace amount of oxygen. The seemingly larger SNR, dominating the lower right of the frame, is the Spaghetti Nebula, cataloged as Simeis 147 and sh2-240. This supernova, only about 3,000 light years away, exploded about 40,000 years ago. Comparatively, even though they appear different sizes, both supernova remnants are not only roughly the same age, but about the same size, too.
Tomorrow’s picture: open space
庞大与娇小的超新星遗迹
影像提供与版权: Stéphane Vetter (Nuits sacrées)
说明: 恒星爆炸后会发生什么事？当恒星爆炸时，会出现庞大火球般向四面八方飞溅的炽热气体。当这些气体冲撞现有的星际物质时，会把它们加热到白炽发光。在这幅摄于摩洛哥 欧凯梅登 天文台的主题影像里，可以看到两个超新星遗迹（SNRs）。影像左上角看似较小的泛蓝足球状星云，为距离地球约11,000光年远的SNR G179.0+02.6，造就它的超新星爆炸则约发生于50,000年前。虽然它的主成分是氢气，不过蓝光却是源自其内微量氧气的辐射。影像右下角看似庞然的意大利面星云，其编录号为Simeis 147和Sharpless 240。这颗超新星距离地球仅约3,000光年，爆炸则发生在40,000年前左右。虽然这二个超新星遗迹在影像里的看似大小有别，但它们的年龄和大小其实很相近。
明日的图片: open space
