2026年2月25日
The Egg Nebula from the Hubble Telescope
Image Credit & Copyright: ESA/Hubble & NASA, B. Balick (U. Washington)
Explanation: Ever wonder what it would look like to crack open the Sun? The Egg Nebula, a dying Sun-like star, can unscramble this question. Pictured is a combination of several visible and infrared images of the nebula (also known as RAFGL 2688 or CRL 2688) taken with the Hubble Space Telescope. The star has shed its outer layers, and a bright, hot core (or “yolk”) now illuminates the milky “egg white” shells of gas and dust surrounding the center. The central lobes and rings are structures of gas and dust recently ejected into space, with the dust being dense enough to block our view of the stellar core. Light beams emanate from that blocked core, escaping through holes carved in the older ejected material by newer, faster jets expelled from the star’s poles. Astronomers are still trying to figure out what causes the disks, lobes, and jets during this short (only a few thousand years!) phase of the star’s evolution, making this an egg-cellent image to study!
Tomorrow’s picture: spiral webb
哈勃太空望远镜拍摄的蛋星云
影像提供与版权: ESA/Hubble & NASA, B. Balick (U. Washington)
说明: 你是否曾经好奇过，如果太阳裂开会是什么样子？蛋星云，一颗垂死的类太阳恒星，或许能为你解开这个谜团。如本图所示，这是由哈勃太空望远镜拍摄的多张可见光与红外线影像合成，此星云亦称为RAFGL 2688或CRL 2688。这颗恒星已经抛掉了外层包壳，明亮炙热的核心（仿佛”蛋黄”）正照亮了环绕其中心的乳白色“蛋白”状气体和尘埃壳层。中央可见的双极叶状与环状结构，是近期抛射到星际空间的气体与尘埃，这些尘埃的密度极高，足以阻挡我们对恒星核心的直视观测。光束从被遮蔽的核心发出，穿过由恒星两极喷射的更新、更快的喷流在较老的喷射物质上刻出的孔洞。天文学家仍在厘清圆盘、双极叶与喷流的成因，而这短暂（仅数千年）的阶段属于恒星的演化历程，也因此这幅影像成了研究此类现象的极佳教材，可谓名副其实的「蛋」定佳作！
明日的图片: spiral webb
