字幕列表 影片播放 列印英文字幕 Could all the water in the Milky Way be used to extinguish the Sun? 71 percent of the Earth's surface is covered with water. According to geologists, if all the water in and on the Earth – in its oceans, icecaps and glaciers, lakes, rivers, groundwater and the water in the atmosphere – were put into one sphere, it would be 860 miles across. That sphere would contain 365 million trillion gallons of water. If all that water was poured on the Sun, would the Sun be extinguished? “Unlikely!” say chemists. Because the Sun is 1.3 million times bigger than the Earth Even if we had thousand times more water, the Sun is so hot it would boil off the water and turn it into vapor. How about if we gathered together all the water in our Milky Way galaxy and poured it on the Sun? “Would that put the fire out?” Well, the Milky Way is full of planets containing water beneath their surfaces and in the form of ice and vapour. And then there is the water in between the stars and planets… contained in interstellar gas and interstellar dust. “Would that be enough?” With a rough calculation, all the water in the Milky Way amounts to a volume 100 million times greater than the volume of the Sun. The water in the Milky Way is also 100 times bigger than the galaxy's biggest black hole. So, imagine if you could pour all the Milky Way's water onto the Sun, surely the Sun would collapse into a huge black hole. This black hole would not be glowing, so you would be able to say that the Sun had been destroyed. Right? Hang on a minute. Maybe not ! Maybe we're looking at this from the wrong angle. Let's turn it around. Can we extinguish the Sun with water? Any solar expert will tell you that the Sun is not even on fire. Our wonderful Sun is simply a nuclear fusion reaction, converting hydrogen atoms into helium under the immense temperatures and pressures at its core. If we were to pour water on it, the added mass would simply increase the pressure at the core and accelerate the nuclear fusion going on in there, producing even more energy. Then again, maybe, instead of getting tangled up in all this hypothetical arithmetic, Perhaps we should just marvel at the beauty of the Milky Way as a whole – through this beautiful photo, for example, taken with a modest smartphone
B1 中級 英國腔 難道銀河系的水都可以用來熄滅太陽? (Could all the water in the milky way be used to extinguish the sun?) 251 8 yunfeicheng1 發佈於 2021 年 01 月 14 日 更多分享 分享 收藏 回報 影片單字