保护地球，探索宇宙，发现文明
While appearing as a delicate and light veil draped across the sky, this image from the NASA/ESA Hubble Space Telescope actually depicts a small section of the Cygnus supernova blast wave, located around 2,400 light-years away. The name of the supernova remnant comes from its position in the northern constellation of Cygnus (the Swan), where it covers an are...
美国宇航局/欧空局哈勃太空望远镜的最新结果表明，早期宇宙中第一批恒星和星系的形成比之前认为的要早。欧洲天文学家还没有发现第一代恒星的证据，也就是所谓的星族Ⅲ，那时宇宙只有5亿年的历史。 探索最早的星系仍然是现代天文学的重大挑战。我们不知道宇宙中最初的恒星和星系是何时或如何形成的。这些问题可以通过哈勃太空望远镜的深度成像观测来解决。哈勃望远镜可以让天文学家将宇宙回溯到大爆炸5亿年内。 美国宇航局/欧空局哈勃太空望远镜的最新结果表明，早期宇宙中第一批恒星和星系的形成比之前认为的要早。欧洲天文学家小组没有发现第一代恒星的证据，也就是第三代恒星，那时宇宙还不到10亿年。这个艺术家的印象呈现了早期的宇宙。 来源：ESA/Hubble, M. Kornmesser and NASA 由欧洲航天局的Rachana Bhata...
Almost like snowflakes, the stars of the globular cluster NGC 6441 sparkle peacefully in the night sky, about 13,000 light-years from the Milky Way’s galactic center. Like snowflakes, the exact number of stars in such a cluster is difficult to discern. It is estimated that together the stars have 1.6 million times the mass of the Sun, making NGC 6441 one of ...
2020 May 11 Behind Betelgeuse Image Credit & Copyright: Adam Block, Steward Observatory, University of Arizona Explanation: What’s behind Betelgeuse? One of the brighter and more unusual stars in the sky, the red supergiant star Betelgeuse can be found in the direction of famous constellation Orion. Betelgeuse, however, is actually well in front o...
2020 March 24 A Black Hole Disrupts a Passing Star Illustration Credit: NASA, JPL-Caltech Explanation: What happens to a star that goes near a black hole? If the star directly impacts a massive black hole, then the star falls in completely — and everything vanishes. More likely, though, the star goes close enough to have the black hole’s gravity ...
根据NASA钱德拉X射线天文台和美国国家科学基金会卡尔·F·杨斯基超大型阵列(VLA)的观测，一个双星系统一直在两个不同的自我之间转换。研究人员使用了将近15年的钱德拉的数据，发现恒星二人组的行为就像一种物体切换其标识，然后在几年后返回其原始状态。这是一个罕见的恒星系统以这种方式改变其行为的例子。 天文学家在密集的恒星群中发现了这个易变的双星系统，即球状星团Terzan 5，它距离地球约2万光年，位于银河系中。这个被称为Terzan 5 CX1的双星有一颗中子星(超新星爆炸后留下的密度极高的残骸)，它围绕着一颗类似太阳的恒星运行，但质量较小。 在这张新的Terzan 5(右)图像中，钱德拉探测到的低、中、高能X射线分别为红色、绿色和蓝色。左边，哈勃太空望远镜拍摄的图像显示了同样的光学视野。Terzan 5 CX...
这个巨型螺旋星系或许会被称为“哥斯拉星系”（Godzilla galaxy），因为该星系有可能是其所在宇宙中已知的最大星系。该星系名为UGC 2885，比银河系宽2.5倍，其恒星数量则是银河系的10倍。 不过研究人员表示，UGC 2885星系是一个“温和的巨人”，因为它看上去没有与其他大型星系碰撞而过着相对静态的生活。在过去数十亿年间，它逐渐从星系间的丝状结构中吸收积累了氢，以缓慢而稳定的速度制造新恒星，其恒星诞生速率约为银河系的一半。事实上，该星系的超大质量中心黑洞也是一个沉睡的巨人。因为该星系似乎并不吞噬比它小得多的卫星星系，从而缺乏流入的气体。 肯塔基州路易斯维尔大学的本尼•霍尔维达（Benne Holwerda）用美国国家航空航天局（NASA）的哈勃太空望远镜对UGC 2885星系进行了观测，并以天文学...
2020 January 12 Stars and Dust in Corona Australis Image Credit & Copyright: CHART32 Team, Processing – Johannes Schedler Explanation: Cosmic dust clouds and young, energetic stars inhabit this telescopic vista, less than 500 light-years away toward the northern boundary of Corona Australis, the Southern Crown. The dust clouds effectively block lig...
Newborn stars, hidden behind thick dust, are revealed in this image of a section of the so-called Christmas Tree Cluster from NASA’s Spitzer Space Telescope. The newly revealed infant stars appear as pink and red specks toward the center and appear to have formed in regularly spaced intervals along linear structures in a configuration that resembles th...
2019 December 24 A Northern Winter Sky Panorama Image Credit & Copyright: Tomas Slovinsky Explanation: What stars shine in Earth’s northern hemisphere during winter? The featured image highlights a number of bright stars visible earlier this month. The image is a 360-degree horizontal-composite panorama of 66 vertical frames taken consecutively wit...