Image credit: ESA/Hubble & NASA; Acknowledgement: Judy Schmidt
NASA’s Hubble Space Telescope captured an uncommon sight – the death of a low-mass star – in this image of the Calabash Nebula released on Feb. 3, 2017.
Here, we can see the star going through a rapid transformation from a red giant to a planetary nebula, during which it blows its outer layers of gas and dust out into the surrounding space. The recently ejected material is spat out in opposite directions with immense speed — the gas shown in yellow is moving close to a million kilometers an hour.
Astronomers rarely capture a star in this phase of its evolution because it occurs within the blink of an eye – in astronomical terms. Over the next thousand years the nebula is expected to evolve into a fully-fledged planetary nebula.
图片来源: ESA/Hubble & NASA; 致谢: Judy Schmidt
NASA哈勃太空望远镜在2017年2月3日发布的这张葫芦星云图像中，捕捉到了一个罕见景象——一颗低质量恒星的死亡过程。
在这里，我们看到这颗恒星正经历从红巨星向行星状星云的快速转变阶段。在此过程中，它将自身外层的气体与尘埃猛烈抛射到周围空间。最新喷出的物质沿相反方向高速飞散，图中呈黄色的气体运动速度接近每小时100万公里。
天文学家极少能在这一演化阶段观测到恒星，因为从天文尺度来看，这一过程只发生在眨眼之间。预计在未来数千年内，这片星云将逐渐演化成一个完全成熟的行星状星云。
