Copyright:Julien Looten
中文翻譯:
你知道嗎？天文學家們可以用激光來幫助他們觀察星星！雖然激光不是用來保護地球的，但它們能幫助我們看得更清楚。在某些方向上，空氣會讓星光變得模糊，這就像在水裡看到的影子一樣。有時候，天空中沒有明亮的星星，這時候，天文學家就會用激光來創造一顆人造星星！通過觀察這顆人造星星，他們可以知道空氣的變化，這樣就能調整望遠鏡的鏡子，讓我們看到的星星、行星和星雲變得更清晰。看看智利的Paranal Observatory，這裡有很多不同顏色的天氣，它們像畫筆一樣在天上塗抹著迷人的色彩，還有我們的銀河系大路在天空中閃耀著！
原文:
Are lasers from giant telescopes being used to defend the Earth? No. Lasers shot from telescopes are now commonly used to help increase the accuracy of astronomical observations. In some directions, Earth atmosphere-induced fluctuations in starlight can indicate how the air mass over a telescope is changing, but in other directions, no bright star exists. In these directions, astronomers can create an artificial star with a laser. Subsequent observations of the artificial laser guide star can reveal information so detailed about the changing blurring effects of the Earth’s atmosphere that much of it can be removed by rapidly flexing a telescope’s mirror. Such adaptive optics techniques allow high-resolution ground-based observations of real stars, planets, and nebulas. Pictured here, telescopes at Paranal Observatory in Chile study a colorful sky filled with green airglow and the Magellanic Clouds on the left, red airglow on the right, and the majestic central band of our Milky Way Galaxy arching across the center.
來源:NASA每日圖片
