2026年2月4日
Spiral Galaxy NGC 1512: Wide Field
Image Credit & Copyright: Daniel Stern
Explanation: Most galaxies don’t have any rings — why does this galaxy have three? To begin, a ring that’s near NGC 1512‘s center — and so hard to see here — is the nuclear ring which glows brightly with recently formed stars. Next out is a ring of stars and dust appearing both red and blue, called, counter-intuitively, the inner ring. This inner ring connects ends of a diffuse central bar of stars that runs horizontally across the galaxy. Farthest out in this wide field image is a ragged structure that might be considered an outer ring. This outer ring appears spiral-like and is dotted with clusters of bright blue stars. All these ring structures are thought to be affected by NGC 1512‘s own gravitational asymmetries in a drawn-out process called secular evolution. The featured image was captured last month from a telescope at Deep Sky Chile in Chile.
Tomorrow’s picture: open space
螺旋星系NGC 1512: 广域视野
影像提供与版权: Daniel Stern
说明: 大多数的星系并没有任何环，为什么这个星系有三个环呢？首先，靠近NGC 1512中心的环是核环，在这里很难看到，它由新形成的恒星组成，发出明亮的光芒。接下来是一个由恒星和尘埃组成的环，呈现出红色和蓝色，与直觉相反，它被称为内环。这个内环连接着一条弥散的中心棒状结构两端，这条棒状结构水平贯穿整个星系。在这张广角影像的最远处，是一个参差不齐的结构，可以被认为是外环。这个外环看起来呈螺旋状，点缀着明亮的蓝色星团。所有这些环状结构都被认为是受到NGC 1512自身重力不对称性的影响，这个过程被称为长期 演化。这张特色影像是上个月由位于智利 深空观测站的望远镜拍摄的。
明日的图片: open space
