The article discusses papers that were published in the journal "Nature" on star formation in galaxies in the early universe. One paper by an international team of astronomers supports a th...
Most galaxies haveblack holesat their centers that can produce a tremendous amount of energy, which astronomers can see over great distances. In some cases, a galaxy’s central black hole isextremely largeor active, even in relatively small galaxies. Material circling the black hole may be accel...
Stars on the main sequence burn by fusing hydrogen into helium. Large stars tend to have higher core temperatures than smaller stars. Therefore, large stars burn the hydrogen fuel in the core quickly, whereas, small stars burn it more slowly. The length of time that they spend on the main ...
The Hubble Space Telescope is deployed from the cargo bay of the space shuttle Have you ever stared at the night sky and wondered what the universe looks like up close? Even if you're lucky enough to have access to a ground-based telescope, whose clarity depends on atmospheric factors ...
How did Earth get such a strange moon? Exploring the giant impact theory Large alien planets may be born in chaos, NASA's retired exoplanet-hunter finds That matches observations that have been made with instruments like NASA's Kepler space telescope. So far, only a handful of rocky worl...
How are elliptical galaxies formed? How did the heliocentric theory impact the Scientific Revolution? How did the Arecibo Observatory telescope collapse? Describe asteroids, meteors, and comets. What is a crater s angular size? How was the Arecibo Observatory built? How did the Kuiper belt form?
How did the planet Mercury form? Why do gas planets have rocky moons? Why do gas planets form first? Why do gas giants form after terrestrial planets? How are elliptical galaxies formed? How are S-type asteroids formed? What is the nebular hypothesis of planet formation?
2.According to the lecture, how did distant galaxies appear to eighteenth-century astronomers? A. Like the moons of planets B. Like small clouds C. Like variable stars D. Like bright points of light 你的答案: 正确答案:B 题目解析: 登录 后才能查看题目解析,还没有账号? 马上注册 推...
down, so we can’t any longer rely on our ordinary understanding of cause and effect either. Despite this, all candidate theories of quantum gravity describe something physical that was going on in the Planck epoch – some quantum precursor of ordinary space and time. But where didthatcome ...
Though we know much more about the processes of galaxy formation and evolution than we did even a decade ago, many key points still elude us. One particular puzzle is that of how star formation ends in a galaxy. We think that galaxies eventually transition from bright, blue, star-forming...