跳至內容

File:Elegant spiral hides a hungry monster.jpg

頁面內容不支援其他語言。
這個檔案來自維基共享資源
維基百科，自由的百科全書

原始檔案 （1,280 × 1,340 像素，檔案大小：407 KB，MIME 類型：image/jpeg）

摘要

描述
English: NGC 4639 is a beautiful example of a type of galaxy known as a barred spiral. It lies over 70 million light-years away in the constellation of Virgo and is one of about 1500 galaxies that make up the Virgo Cluster.

In this image, taken by the NASA/ESA Hubble Space Telescope, one can clearly see the bar running through the bright, round core of the galaxy. Bars are found in around two thirds of spiral galaxies, and are thought to be a natural phase in their evolution.

The galaxy’s spiral arms are sprinkled with bright regions of active star formation. Each of these tiny jewels is actually several hundred light-years across and contains hundreds or thousands of newly formed stars. But NGC 4639 also conceals a dark secret in its core — a massive black hole that is consuming the surrounding gas.

This is known as an active galactic nucleus (AGN), and is revealed by characteristic features in the spectrum of light from the galaxy and by X-rays produced close to the black hole as the hot gas plunges towards it.

Most galaxies are thought to contain a black hole at the centre. NGC 4639 is in fact a very weak example of an AGN, demonstrating that AGNs exist over a large range of activity, from galaxies like NGC 4639 to distant quasars, where the parent galaxy is almost completely dominated by the emissions from the AGN.
日期
來源 http://www.spacetelescope.org/images/potw1541a/
作者 ESA/Hubble & NASA

授權條款

w:zh:共享創意
姓名標示
姓名標示
 ESA/Hubble images, videos and web texts are released by the ESA under the Creative Commons Attribution 4.0 International license and may on a non-exclusive basis be reproduced without fee provided they are clearly and visibly credited. Detailed conditions are below; see the ESA copyright statement for full information. For images created by NASA or on the hubblesite.org website, or for ESA/Hubble images on the esahubble.org site before 2009, use the {{PD-Hubble}} tag.
Conditions:
  • The full image or footage credit must be presented in a clear and readable manner to all users, with the wording unaltered (for example: "ESA/Hubble"). Web texts should be credited to ESA/Hubble (except when used by media). The credit should not be hidden or disassociated from the image footage. Links should be active if the credit is online. See the usage rights Q&A section on the ESA copyright page for guidance.
  • ESA/Hubble materials may not be used to state or imply the endorsement by ESA/Hubble or any ESA/Hubble employee of a commercial product or service.
  • ESA/Hubble requests a copy of the product sent to them to be indexed in their archive.
  • If an image shows an identifiable person, using that image for commercial purposes may infringe that person's right of privacy, and separate permission should be obtained from the individual.
  • If images or visuals are changed significantly from the original work (apart from resizing, cropping), we suggest that the changes are mentioned after the credit line. For example "Original image by ESA/Hubble (M. Kornmesser), warping and recolouring by NN".

Notes:

  • Note that this general permission does not extend to the use of ESA/Hubble's logo, which shall remain protected and may not be used or reproduced without prior and individual written consent of ESA/Hubble.
  • Also note that music, scientific papers and code on the esahubble.org site are not released under this license and can not be used for non-ESA/Hubble products.
  • By reproducing ESA/Hubble material, in part or in full, the user acknowledges the terms on which such use is permitted.
w:zh:共享創意
姓名標示
此檔案採用創用CC 姓名標示 4.0 國際授權條款。
姓名標示: ESA/Hubble
您可以自由：
  • 分享 – 複製、發佈和傳播本作品
  • 重新修改 – 創作演繹作品
惟需遵照下列條件：
  • 姓名標示 – 您必須指名出正確的製作者，和提供授權條款的連結，以及表示是否有對內容上做出變更。您可以用任何合理的方式來行動，但不得以任何方式表明授權條款是對您許可或是由您所使用。

說明

添加單行說明來描述出檔案所代表的內容

在此檔案描寫的項目

描繪內容

沒有維基數據項目的某些值

著作權狀態 繁體中文 (已轉換拼寫)

有著作權 繁體中文 (已轉換拼寫)

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⁠圖尺寸用戶備⁠註
目前2015年10月13日 (二) 08:24於 2015年10月13日 (二) 08:24 版本的縮圖1,280 × 1,340（407 KB）JmencisomUser created page with UploadWizard

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：

詮釋資料

此檔案中包含擴展的資訊。這些資訊可能是由數位相機或掃描器在建立時或數位化過程中所加入。

如果此檔案的來源檔案已被修改，一些資訊在修改後的檔案中將不能完全反映出來。

取自 "https://zh.wikipedia.org/wiki/File:Elegant_spiral_hides_a_hungry_monster.jpg"