新加坡国立大学网课代修:紫外线发射

凯克利用天文学家想要回答的另一个问题是“第一个星系是如何形成的?”由于这些婴儿星系离我们很远,并且是遥远宇宙的一部分,因此很难观察它们。首先,它们非常暗淡。其次,它们的光被宇宙的膨胀“拉伸”,对我们来说,它们出现在红外线中。然而,了解它们可以帮助我们了解我们的银河系是如何形成的。凯克可以用红外敏感仪器观察那些遥远的早期星系。除此之外,他们还可以研究那些星系中的热年轻恒星发出的光(紫外线发射),这些星系是由年轻星系周围的气体云重新发射出来的。这让天文学家能够深入了解这些遥远恒星城市的状况,当时他们只是婴儿,刚刚开始成长。天文台的历史可以追溯到20世纪70年代初。那时天文学家开始着眼于建造新一代大型地面望远镜,他们可以创造出最大的镜子。然而,玻璃镜子可能非常重且移动时很笨重。科学家和工程师想要的是轻量级的。参与加州大学和劳伦斯伯克利实验室的天文学家正在研究制造柔性镜子的新方法。他们提出了一种方法,通过创建可以成角度和“调整”以创建一个更大镜子的分段镜像来实现。第一面镜子叫做Keck I,于1993年5月开始观测天空.Keck II于1996年10月开放。从那时起,这些反射望远镜一直在使用。 新加坡国立大学网课代修:紫外线发射 Another question that Keck uses astronomers to answer is “How did the first galaxy form?” Because these baby galaxies are far away from us and part of the distant universe, it is difficult to observe them. First of all, they are very dim. Second, their light is "stretched" by the expansion of the universe, and for us, they appear in the infrared. However, understanding them can help us understand how our Milky Way is formed. Keck can observe those distant early galaxies with infrared-sensitive instruments. In addition, they can study the light (ultraviolet emissions) from hot young stars in those galaxies that are re-emitted by gas clouds around young galaxies. This allowed astronomers to gain insight into the conditions of these distant stellar cities, when they were just babies and just started to grow. The history of the Observatory dates back to the early 1970s. At that time, astronomers began to focus on building a new generation of...
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