Image:TwilightLength.png
From Wikipedia, the free encyclopedia
Size of this preview: 800 × 584 pixels
Full resolution (1,096 × 800 pixels, file size: 171 KB, MIME type: image/png)
| This is a file from the Wikimedia Commons. The description on its description page there is shown below.
|
[edit] Summary
| Description |
Length of civil twilight, in hours, as a function of latitude and time of year. Civil twilight begins before sunrise when the sun is geometrically 6 degrees below the horizon and ends after sunset when the sun is geometrically 6 degrees below the horizon, and is roughly the period during which, under clear skies, outdoor activities can be carried out without artificial light. Note the times in March and September where continous civil twilight is present at locations close to either pole Times were calculated using the FORTRAN program sunae.f found at ftp://climate1.gsfc.nasa.gov/wiscombe/Solar_Rad/SunAngles/sunae.f. Contours are not necessarily smooth because of the 0.5-degree latitude spacing used in the calculations. Calculations were performed for the 365 days in 2007 on the Greenwich Meridian. |
|---|---|
| Source |
self-made |
| Date |
5 September 2007 |
| Author | |
| Permission (Reusing this image) |
see below |
SVG version available, but it seems to load very slowly: Image:TwilightLength.svg
[edit] Licensing
 |
I, the copyright holder of this work, hereby release it into the public domain. This applies worldwide. In case this is not legally possible: Afrikaans | Alemannisch | Aragonés | العربية | Asturianu | Български | Català | Česky | Cymraeg | Dansk | Deutsch | Eʋegbe | Ελληνικά | English | Español | Esperanto | Euskara | Estremeñu | فارسی | Français | Galego | 한국어 | हिन्दी | Hrvatski | Ido | Bahasa Indonesia | Íslenska | Italiano | עברית | Kurdî / كوردی | Latina | Lietuvių | Latviešu | Magyar | Македонски | Bahasa Melayu | Nederlands | Norsk (bokmål) | Norsk (nynorsk) | 日本語 | Polski | Português | Ripoarisch | Română | Русский | Shqip | Slovenčina | Slovenščina | Српски / Srpski | Svenska | ไทย | Tagalog | Türkçe | Українська | Tiếng Việt | Walon | 中文(简体) | 中文(繁體) | zh-yue-hant | +/- |
File history
Click on a date/time to view the file as it appeared at that time.
| Date/Time | Dimensions | User | Comment | |
|---|---|---|---|---|
| current | 05:09, 6 September 2007 | 1,096×800 (171 KB) | StephenHudson | ({{Information |Description=Length of civil twilight as a function of latitude and time of year. Civil twilight begins before sunrise when the sun is geometrically 6 degrees below the horizon and ends after sunset when the sun is geometrically 6 degrees be) |
