File:Yepun’s Laser and the Magellanic Clouds.jpg
原始檔案 (4,057 × 6,026 像素,檔案大小:5.33 MB,MIME 類型:image/jpeg)
摘要
描述Yepun’s Laser and the Magellanic Clouds.jpg |
English: One of the major enemies of astronomers is the Earth’s atmosphere, which makes celestial objects appear blurry when observed by ground-based telescopes. To counteract this, astronomers use a technique called adaptive optics, in which computer-controlled deformable mirrors are adjusted hundreds of times per second to correct for the distortion of the atmosphere.
This spectacular image shows Yepun,[1] the fourth 8.2-metre Unit Telescope of ESO’s Very Large Telescope (VLT) facility, launching a powerful yellow laser beam into the sky. The beam creates a glowing spot — an artificial star — in the Earth’s atmosphere by exciting a layer of sodium atoms at an altitude of 90 km. This Laser Guide Star (LGS) is part of the VLT’s adaptive optics system. The light coming back from the artificial star is used as a reference to control the deformable mirrors and remove the effects of atmospheric distortions, producing astronomical images almost as sharp as if the telescope were in space. Yepun’s laser is not the only thing glowing brightly in the sky. The Large and Small Magellanic Clouds can be seen, to the left and to the right of the laser beam, respectively. These nearby irregular dwarf galaxies are conspicuous objects in the southern hemisphere, and can be easily observed with the unaided eye. The prominent bright star to the left of the Large Magellanic Cloud is Canopus, the brightest star in the constellation Carina (The Keel), while the one towards the top-right of the image is Achernar, the brightest in the constellation Eridanus (The River). This image was taken by Babak Tafreshi, an ESO Photo Ambassador.
|
日期 | (released) |
來源 | http://www.eso.org/public/images/potw1225a/ |
作者 | ESO/B. Tafreshi/TWAN |
授權條款
This media was created by the European Southern Observatory (ESO).
Their website states: "Unless specifically noted, the images, videos, and music distributed on the public ESO website, along with the texts of press releases, announcements, pictures of the week, blog posts and captions, are licensed under a Creative Commons Attribution 4.0 International License, and may on a non-exclusive basis be reproduced without fee provided the credit is clear and visible." To the uploader: You must provide a link (URL) to the original file and the authorship information if available. | |
此檔案採用創用CC 姓名標示 4.0 國際授權條款。
|
在此檔案描寫的項目
描繪內容
創用CC姓名標示4.0國際 繁體中文 (已轉換拼寫)
18 6 2012
檔案歷史
點選日期/時間以檢視該時間的檔案版本。
日期/時間 | 縮圖 | 尺寸 | 使用者 | 備註 | |
---|---|---|---|---|---|
目前 | 2012年10月15日 (一) 11:37 | 4,057 × 6,026(5.33 MB) | Stas1995 | ||
2012年10月15日 (一) 11:36 | 2,693 × 4,000(4.25 MB) | Stas1995 | |||
2012年6月18日 (一) 13:13 | 1,280 × 1,901(534 KB) | Jmencisom |
檔案用途
下列頁面有用到此檔案:
全域檔案使用狀況
以下其他 wiki 使用了這個檔案:
- de.wikipedia.org 的使用狀況
詮釋資料
此檔案中包含其他資訊,這些資訊可能是由數位相機或掃描器在建立或數位化過程中所新增的。若檔案自原始狀態已被修改,一些詳細資料可能無法完整反映出已修改的檔案。
來源 | European Southern Observatory |
---|---|
製作/提供者 | ESO/B. Tafreshi (twanight.org) |
影像標題 |
|
簡稱 |
|
使用條款 |
|
資料產生的日期時間 | 2012年6月18日 (一) 10:00 |
關鍵字 |
|
聯絡資訊 |
Karl-Schwarzschild-Strasse 2 Garching bei München, , D-85748 Germany |