Astronomical Info / 天文資訊 > Special Events / 特別項目 > Partial Lunar Eclipse of August 8th, 2017 | 2017 年 8 月 8 日之月偏食 [Refresh 更新]
Quick info 快速資訊: Eclipse time (partial phase) at Hong Kong 香港可見月食 (偏食) 時間 : 2017/08/08 01:23 - 03:18 HKT
Quick links 快速連結:- Live webcast 網上直播 | - Information about the eclipse 是次月食資料 |
- Local (HK) circumstances 本地 (香港) 情況 | - Future lunar eclipses 未來月食 |
- Lunar eclipse basic knowledge 月食基礎知識 | - More eclipse info 更多日月食資訊 |
Live webcast 網上直播 |
Please click on the links below for live webcast and descriptions of the event. All links (on the left panel) redirect you to external websites and open in new windows.
請按下列連結以觀看網上直播及相關資訊。所有 (左方) 連結連至第三者網站並以新視窗開啟。
Provider 提供者 | Notes 備註 |
- HKO and others 香港天文台與其他機構 | |
- Taipei Astronomical Museum 台北天文館 | |
- Slooh.com | |
- Virtual Telescope |
Information about the eclipse 是次月食資料 |
This is the first non-penumbral eclipse of the moon since September 2015. The partial eclipse will be visible in its entirety in eastern Africa, most of Asia and Oceania. Europe and the rest of Africa will experience the event at moonrise, while observers in eastern Asia and New Zealand will see the eclipse at moonset. The eclipse is not visible at all in the Americas.
The partial phase will last less than 2 hours, during which about 20% of the moon will be hidden from view. The penumbral phase will last much longer, extending to 1.5 hours both before and after the partial eclipse.
這是自 2015 年 9 月以來的首次非半影月食。東非、亞洲大部分地區及大洋洲將可見整個月食過程;歐洲及非洲其餘地區將見帶食月出,而亞洲東端及紐西蘭則見帶食月落。是次月食於美洲並不可見。
偏食階段歷時少於 2 小時,期間月球約兩成面積將被食去。半影食歷時較長,於偏食前後各 1.5 小時間可見。
Map courtesy of NASA
月食圖由美國太空總署提供 |
The following shows some general details about the eclipse:
下表列出是次月食的一般性資料 :
All places that can observe this eclipse (no matter what the Moon's position is) will experience the aforementioned events in the times indicated above.
所有可以看見月食的地點均會在上述時間看見該等事件。
Local (HK) circumstances 本地 (香港) 情況 |
In Hong Kong, the penumbral phase will start just before midnight August 8. Partial eclipse will begin at 1:22 am and maximum eclipse will occur around 1 hour later. The moon will be fully visible at 3:18 am, and the penumbral phase will end at 4:51 am. As the lunar altitude is not low during the eclipse, locations reasonably open towards the southwest are ideal for observation.
香港方面,半影食將於 8 月 8 日午夜前開始。偏食於上午 1 時 22 分開始,約 1 小時後到達食甚。月球將於上午 3 時 18 分復圓,而半影食將於上午 4 時 51 分完結。由於月食時月球仰角不低,西南面沒有太大遮擋的地方已可觀賞是次月食。
The details are summarized in the following table:
詳細資料整理如下 :
Event for Hong Kong 在香港看到的事件 |
Time in HKT 香港時間 |
Lunar Altitude and Azimuth 月球的高度和方位角 |
Moon enters Earth's penumbra (penumbral eclipse starts) 月球進入地球的半影 (半影月食開始) |
Aug 7 23:50:02 | Altitude 高度 : 51° Azimuth 方位角 : 167° (SSE 東南偏南) |
Moon enters Earth's umbra (partial eclipse starts) 月球進入地球的本影 (初虧,月偏食開始) |
Aug 8 01:22:55 | Altitude 高度 : 49° Azimuth 方位角 : 201° (SSW 西南偏南) |
Greatest eclipse |
Aug 8 02:20:28 | Altitude 高度 : 43° Azimuth 方位角 : 219° (SW 西南) |
Moon leaves Earth's umbra (partial eclipse ends) 月球離開地球的本影 (復圓,月偏食結束) |
Aug 8 03:18:10 | Altitude 高度 : 33° Azimuth 方位角 : 231° (SW 西南) |
Moon leaves Earth's penumbra (penumbral eclipse ends) 月球離開地球的半影 (半影月食結束) |
Aug 8 04:50:56 | Altitude 高度 : 16° Azimuth 方位角 : 245° (WSW 西南偏西) |
Information at greatest magnitude for Hong Kong 香港在最大食分時的資料 |
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Type 類型 | Partial 月偏食 | |
Time 時間 | 02:20 HKT | |
Direction of shadow relative to the Moon 地球影子方向 (相對於月球) | Entering and leaving from the bottom left 由月球的左下方進入及離開 |
Future lunar eclipses 未來月食 |
Lunar eclipses in the next five years (click on the date to see the visible areas for that eclipse):
未來五年的月食資料 (請按下日期以觀看月食可見範圍) :
Date (UTC) 日期 (世界協調時) |
Eclipse type 月食類型 |
Magnitude* 食分* |
Eclipse type at HK 香港可見月食類型 |
Time of greatest eclipse 食甚時香港時間 |
2018/01/31 | Total 月全食 | P: 2.2941; U: 1.3155 | Total 月全食 | 21:30 |
2018/07/27 | Total 月全食 | P: 2.6792; U: 1.6087 | Total 月全食 | 07/28 04:21 |
2019/01/21 | Total 月全食 | P: 2.1684; U: 1.1953 | --- | --- |
2019/07/16 | Partial 月偏食 | P: 1.7037; U: 0.6531 | Partial 月偏食 | 07/17 05:31 |
2020/01/10 | Penumbral 半影月食 | P: 0.8956; U: -0.1160 | Penumbral 半影月食 | 01/11 03:10 |
2020/06/05 | Penumbral 半影月食 | P: 0.5683; U: -0.4053 | Penumbral 半影月食 | 06/06 03:25 |
2020/07/05 | Penumbral 半影月食 | P: 0.3546; U: -0.6436 | --- | --- |
2020/11/30 | Penumbral 半影月食 | P: 0.8285; U: -0.2620 | Penumbral 半影月食 | 17:43 |
2021/05/26 | Total 月全食 | P: 1.9540; U: 1.0095 | Total 月全食 | 19:19 |
2021/11/19 | Partial 月偏食 | P: 2.0720; U: 0.9742 | Partial 月偏食 | 17:37 (moonrise 月出) |
2022/05/16 | Total 月全食 | P: 2.3726; U: 1.4137 | --- | --- |
* P represents penumbral magnitude while U represents umbral magnitude.
* P 和 U 分別代表半影食分和本影食分。
There will be two total lunar eclipses in 2018, both of which are visible in Hong Kong.
2018 年將出現兩次月全食,於香港皆可見。
Lunar eclipse basic knowledge 月食基礎知識 |
The following information is quoted from Wikipedia. 以下資料摘自維基百科。
A lunar eclipse occurs whenever the Moon passes through some portion of the Earth's shadow. This can occur only when the Sun, Earth, and Moon are aligned exactly, or very closely so, with the Earth in the middle. Hence, there is always a full moon the night of a lunar eclipse. The type and length of an eclipse depend upon the Moon's location relative to its orbital nodes.
月食,又作月蝕,是當月球運行進入地球的陰影(本影部份)時,原本可被太陽光照亮的部份,有部份或全部不能被直射陽光照亮,使得位於地球的觀測者無法看到普通的月相的天文現象。月食發生時,太陽、地球、月球恰好或幾乎在同一條直線上,因此月食必定發生在滿月的晚上(農曆十五、十六、或十七)。地球陰影位於地球公轉軌道面(黃道面)內,此平面與月球軌道面(白道面)並不重合,黃白道面交角約5度;大多數滿月時,月球不在黃道面內,而是或偏北或偏南,不在地球陰影內,因此並不是每個滿月時,都發生月食。每年發生至少兩次月食。
The shadow of the Earth can be divided into two distinctive parts: the umbra and penumbra. Within the umbra, there is no direct solar radiation. However, as a result of the Sun's large angular size, solar illumination is only partially blocked in the outer portion of the Earth's shadow, which is given the name penumbra.
A penumbral eclipse occurs when the Moon passes through the Earth's penumbra. The penumbra does not cause any noticeable darkening of the Moon's surface, though some may argue it turns a little yellow. A special type of penumbral eclipse is a total penumbral eclipse, during which the Moon lies exclusively within the Earth's penumbra. Total penumbral eclipses are rare, and when these occur, that portion of the Moon which is closest to the umbra can appear somewhat darker than the rest of the Moon.
A partial lunar eclipse occurs when only a portion of the Moon enters the umbra. When the Moon travels completely into the Earth's umbra, one observes a total lunar eclipse. The Moon's speed through the shadow is about one kilometer per second (2,300 mph), and totality may last up to nearly 107 minutes. Nevertheless, the total time between the Moon's first and last contact with the shadow is much longer, and could last up to 3.8 hours. The relative distance of the Moon from the Earth at the time of an eclipse can affect the eclipse's duration. In particular, when the Moon is near its apogee, the farthest point from the Earth in its orbit, its orbital speed is the slowest. The diameter of the umbra does not decrease much with distance. Thus, a totally-eclipsed Moon occurring near apogee will lengthen the duration of totality.
The Moon does not completely disappear as it passes through the umbra because of the refraction of sunlight by the Earth's atmosphere into the shadow cone; if the Earth had no atmosphere, the Moon would be completely dark during an eclipse. The red colouring arises because sunlight reaching the Moon must pass through a long and dense layer of the Earth's atmosphere, where it is scattered. Shorter wavelengths are more likely to be scattered by the small particles, and so by the time the light has passed through the atmosphere, the longer wavelengths dominate. This resulting light we perceive as red. This is the same effect that causes sunsets and sunrises to turn the sky a reddish colour; an alternative way of considering the problem is to realise that, as viewed from the Moon, the Sun would appear to be setting (or rising) behind the Earth.
The amount of refracted light depends on the amount of dust or clouds in the atmosphere; this also controls how much light is scattered. In general, the dustier the atmosphere, the more that other wavelengths of light will be removed (compared to red light), leaving the resulting light a deeper red colour. This causes the resulting coppery-red hue of the Moon to vary from one eclipse to the next. Volcanoes are notable for expelling large quantities of dust into the atmosphere, and a large eruption shortly before an eclipse can have a large effect on the resulting colour.
月食有三種類型:
由於地球的本影比月球大得多,這也意味著在發生月全食時,月球會完全進入地球的本影區內,所以不會出現月環食這種現象。
月食過程:
月偏食沒有食既、生光過程,食甚也只表示最接近地球陰影的時刻。
Please read the Wikipedia article for more. 欲得到更多資料,請瀏覽相關條目。
More eclipse info 更多日月食資訊 |
For more information on eclipses, visit our "Eclipse Q&A" section (total 3 pages) and "Eclipse Dates and Numbers - Lunar Eclipse".
如欲得知更多有關日月食的資訊,請到本網的 "日月食問與答" 一節 (共三頁) 和 "月食日期和數字"。
Eclipse times and information are based on Eclipse Predictions by Fred Espenak, NASA's GSFC. NASA's lunar eclipse page: here.
Last Accessed 最近訪問日期: Sun Sep 08 2024 11:47:44 HKT
Last Modified 最近修訂日期: Mon Jul 24 2023