英語聽力文摘560 為何星星會閃爍？
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- 參考譯文
If you’ve ever glanced skyward on a clear evening, you’ve probably noticed with some wonderment the sheer numbers of stars. Some are tiny, barely visible points. Others radiate strong white light. And from our earthly vantage point, these points of light seem fixed.
But, of course, stars and other celestial objects grow brighter and dimmer over time. Now, a massive new data set collected by astronomers at the California Institute of Technology and the University of Arizona documents the brightening and dimming of more then 200 million heavenly bodies.
The data come from images captured by a large telescope in Arizona looking for Near Earth Objects, or NEOs in other words, asteroids whose proximity to Earth could be cause for alarm.
Information about how celestial objects dim and brighten was a fortunate byproduct of the asteroid hunt. And it’s now proving valuable for helping astronomers and other scientists understand more about the evolution of stars, black holes, and the structure of the Milky Way.
For example, the data include information about more than 1,000 exploding stars, or supernovas. Being able to observe, as it were, how supernovas play out by measuring the increasing intensity of their brightness over time, allows scientists to better understand the life and death of stars.
And that’s only one example. As more scientists mine the data, new discoveries about how the heavens work are sure to follow.
為何星星會閃爍?
某個晴朗的夜晚，抬頭瞥一眼夜空，你可能會驚奇地發(fā)現滿天繁星。有些小到難以看見。其他一些恒星則發(fā)出強烈的白光。從地球這一有利視角看去，這些光點似乎總是這么亮。
但是，星星和其它天體當然會隨著時間的推移逐漸變得明亮或是昏暗。如今，加州理工學院和亞利桑那大學的天文學家已搜集了大量數據，它們記錄了2億多天體變得明亮和黯淡的過程。
這些數據源自于科學家在亞利桑那州用大型望遠鏡探測近地天體，也就是NEOs時捕捉的衛(wèi)星圖片，近地天體是指那些接近地球時有可能會對地球構成威脅的小行星。
有關天體如何明暗變幻的信息是科學家探測小行星時意外的收獲。如今，這一收獲在幫助天文學家和其他科學家深入了解恒星，黑洞和銀河系的演變過程方面有重要價值。
例如，這些數據涵蓋了1千多個爆發(fā)星體，或稱為超星體的信息。的確，人們可以通過觀測并對比日益變亮的超星體的亮度來弄清它們爆發(fā)的過程 ，從而進一步了解星辰的誕生和滅亡。
這只是其中的一枚例子。隨著越來越多的科學家探測相關數據，關于蒼穹演變史的新發(fā)現指日可待。
