Glossary term: 日食
Description: 若地球、月球和太陽排成一條直線，且月球位於地球和太陽之間，則會發生日食。從地球表面觀測時，月球圓面覆蓋了天空中的太陽圓面；在太空中觀測時，我們可以看到月球的影子在地球的晝半球上移動。
日食有不同的類型。日全食是指月球圓面完全覆蓋太陽；日偏食是指即使在食甚時，太陽圓面也只有一部分被覆蓋；日環食是指月球與地球的距離比平均值遠，因此看起來比平時小，即使在食甚時也能看到太陽圓面的一圈圓環。
日全食期間，地球上月影最暗處稱為“本影”，月影邊緣稱為“半影”。位於本影內的觀測者看到的是日全食，而位於半影內的觀測者看到的是日偏食。
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Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher The translation of this term and its definition is still awaiting approval
This is an automated transliteration of the simplified Chinese translation of this term
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In Other Languages
- 阿拉伯語: الكسوف الشمسي
- 德語: Sonnenfinsternis
- 英語: Solar Eclipse
- 法語: Eclipse solaire
- 義大利語: Eclissi solare
- 日語: 日食 (external link)
- 簡體中文: 日食
Related Media
日全食
Caption: 這張照片記錄了在孟加拉國庫里格拉姆觀測到的日全食。日食發生時，從地球上看，月球經過太陽前方時。儘管月球的體積遠小於太陽，但由於月球距離地球更近，兩者的角直徑幾乎相同（約為半根手指的寬度）。因此，當月球恰好位於太陽和地球之間時，能夠完全遮住太陽的盤面。環繞黑色圓盤的光環被稱為日冕。
Credit: 盧特法爾-拉赫曼-尼爾哈爾
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License: CC-BY-3.0 Creative Commons Attribution 3.0 Unported icons
Transit of Phobos from Mars
Caption: This video shows the Sun viewed from Mars as Mars’ moon Phobos transits across the solar disk. This video is composed of images taken from the Martian surface on the 30th of September 2024 by the Mastcam-Z camera of NASA’s Perseverance Mars rover. While our Moon is perfectly sized to eclipse the Sun when seen from the Earth’s surface, Phobos’s size and orbit mean that it cannot cover the solar disk completely. This means that this event is a transit and not an eclipse.
This video is in real time, with the entire transit lasting just 32 seconds. This compares with the several hours a solar eclipse on Earth takes from the Moon first obscuring part of the Sun to the Sun being completely visible again. This is due to Phobos’ much shorter orbital period of just over seven and a half hours compared to the Moon’s orbital period of 27 days as well as the solar disk appearing slightly smaller from Mars than it does from Earth. Note the non-spherical shape of Phobos as it crosses the solar disk.
Credit: NASA/JPL-Caltech/ASU/MSSS
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License: PD Public Domain icons
A total solar eclipse over the La Silla Observatory, Chile
Caption: A real-time video showing the total solar eclipse on the 2nd of July 2019 over the La Silla Observatory in Chile. This video covers the moments before totality, the just under two minutes of totality, and the moments after totality. Note that at the start of the video the Sun was already almost completely obscured by the Moon, it is just hard to see due to the brightness of the Sun and the exposure of the camera. Indeed the Moon started partially eclipsing the Sun roughly an hour before the start of this recording and would continue to partially obscure the Sun for roughly the same time afterwards.
At the point of totality one can see the faint glow of the Sun’s diffuse outer regions and on the horizon one can also see the glow from the parts of the surrounding areas on Earth that are not experiencing totality.
Credit: ESO/A. Santerne
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License: CC-BY-4.0 Creative Commons 姓名標示 4.0 國際 (CC BY 4.0) icons
2024 Total Solar Eclipse from Space
Caption: The NASA Deep Space Climate Observatory (DSCOVR) captured the total solar eclipse over North America on the 8th of April, 2024 from space using its Earth Polychromatic Imaging Camera (EPIC). This video shows images of Earth taken over the course of four and a half hours. The Moon’s shadow on the Earth can be seen as it moves from south-west to north east. While the shadow looks like it covers a huge part of the continent, only a strip up to 185 km wide in the middle of the eclipse's path saw a total eclipse at some point on this day and at any one time only the central part of the shadow would have experienced a total solar eclipse. Most of the area covered by this shadow only saw a partial eclipse.
DSCOVR sits at L1, a stable gravitational point between the Sun and Earth and observes the day side of the Earth.
Credit: NASA/DSCOVR EPIC team/Michala Garrison and Wanmei Liang
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License: PD Public Domain icons
Total Solar Eclipse from Casper, Wyoming, USA
Caption: This video shows the total solar eclipse of the 21st of August 2017 observed from Casper, Wyoming, USA by a team of astronomers from the European Space Agency (ESA). This video has been sped up considerably, in reality the moment of totality lasted just under two and a half minutes while the time from the Moon first appearing to obscure the Sun until the Sun was completely unobscured was two hours and 48 minutes.
Before the eclipse we can see several sunspots on the Sun. The Moon moves across the Sun, covering the whole solar disk visible from the point on the Earth this video was taken from. At totality we can see the diffuse solar corona which is normally outshone by the bright solar disk.
Note that while edges of the Sun appear brighter just before and just after totality, this is due to exposure time of the camera being adjusted to make the features visible at totality more obvious. Towards the end of the video some thin cloud begins to affect the observations.
Credit: Video credit: ESA/CESAR ; Music copyright: Flight Of The Angel 3 by Chris Blackwell, audionetwork.com
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License: CC-BY-SA-3.0-IGO Creative Commons Attribution-ShareAlike 3.0 IGO icons
