Astronomy Picture of the Day——灭亡的船底座η

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2019 March 5

DoomedStar Eta Carinae

ImageCredit: NASA, ESA, Hubble; Processing & License: Judy Schmidt

Explanation:Eta Carinae may be about to explode. But no one knows when - it may be nextyear, it may be one million years from now. Eta Carinae's mass - about 100times greater than our Sun - makes it an excellent candidate for a full blownsupernova. Historical records do show that about 170 years ago Eta Carinaeunderwent an unusual outburst that made it one of the brightest stars in thesouthern sky. Eta Carinae, in the Keyhole Nebula, is the only star currentlythought to emit natural LASER light. This featured image brings out details inthe unusual nebula that surrounds this rogue star. Diffraction spikes, causedby the telescope, are visible as bright multi-colored streaks emanating fromEta Carinae's center. Two distinct lobes of the Homunculus Nebula encompass thehot central region, while some strange radial streaks are visible in redextending toward the image right. The lobes are filled with lanes of gas anddust which absorb the blue and ultraviolet light emitted near the center. Thestreaks, however, remain unexplained.

灭亡的船底座η

解释：船底座η可能即将爆发，但没人知道究竟何时爆发，可能是明年，也可能是100万年之后。船底座η的质量比太阳质量大约100倍，使得它成为完全爆发的超新星的完美候选者。历史纪录显示，约170年前，船底座η经历了一次异常的爆发，使得它成为南半球天空中最亮的恒星之一。船底座η在钥匙孔星云中，是目前认为辐射自然激光的唯一恒星。这幅特征影像带出围绕这颗调皮恒星的异常星云中的细节。望远镜引起的衍射光芒，呈现为从船底座η的中心辐射的明亮而多彩的条纹。