保护地球，探索宇宙，发现文明
2021年8月23日 Abell 3827: Cannibal Cluster Gravitational Lens Image Credit: ESA/Hubble & NASA, R. Massey Explanation: Is that one galaxy or three? Toward the right of the featured Hubble image of the massive galaxy cluster Abell 3827 is what appears to be a most unusual galaxy — curved and with three centers. A detailed analysis, however, finds that ...
2021年04月11日 When Black Holes Collide Video Credit & Copyright: Simulating Extreme Spacetimes Collaboration Explanation: What happens when two black holes collide? This extreme scenario occurs in the centers of many merging galaxies and multiple star systems. The featured video shows a computer animation of the final stages of such a merger, while highli...
2020年8月26日 Cygnus Skyscape Image Credit & Copyright: Alistair Symon Explanation: In brush strokes of interstellar dust and glowing hydrogen gas, this beautiful skyscape is painted across the plane of our Milky Way Galaxy near the northern end of the Great Rift and the constellation Cygnus the Swan. Composed using 22 different images and over 180 hours o...
2019 October 26 Gravity’s Grin Image Credit: X-ray – NASA / CXC / J. Irwin et al. ; Optical – NASA/STScI Explanation: Albert Einstein’s general theory of relativity, published over 100 years ago, predicted the phenomenon of gravitational lensing. And that’s what gives these distant galaxies such a whimsical appearance, seen thro...
通过引力透镜（gravitational lensing），来自每个类星体（quasars）的光的产生了多个它的图像。 Image credit: NASA/CXC/Univ. of Oklahoma/X. Dai et al. 就像海洋中的漩涡一样，宇宙中旋转的黑洞在它们周围形成一波“洪流”。不同的是，黑洞将产生的气体尘埃盘加热到数亿度而发出高能X射线。 利用NASA钱德拉X射线天文台（Chandra X-ray Observatory）的数据和一些星系的位置巧合，天文学家采用“引力透镜”来测量五个超大质量黑洞（supermassive black holes）的自旋（spin）。其中一个黑洞周围物质的旋转速度大于光速的70％左右。 引力透镜是一种自然现象。正如爱因斯坦所预测的那样，大质量物体（比如大星系）会...