Remember what Bilbo used to say...

" It's a dangerous business, Frodo, going out your door. You step onto the road, and if you don't keep your feet, there's no knowing where you might be swept off to."





Friday, December 02, 2011

Total lunar eclipse in Hong Kong on December 10


Total lunar eclipse in Hong Kong on December 10
(24 November 2011)

A total lunar eclipse will occur at night on December 10 (Saturday) and will be visible in Hong Kong if the weather is fine.

Scientific Officer of the Hong Kong Observatory, Mr Woo Wang-chun, said, "The duration of the whole process (from the moon entering the penumbra to leaving the penumbra) will last six hours, the longest period of lunar eclipse visible in Hong Kong since the year 2000. As the elevation of the moon will be rather high during the eclipse, most places with an unobstructed view to the east are suitable for viewing the event. If the weather is fine, the condition will be very favourable for viewing the eclipse."

"The moon will not completely disappear but will appear coppery-red in colour during totality. This is because sunlight scattered or refracted by the Earth's atmosphere will be projected onto the moon," said Mr Woo.

A webcast of the event, covering the time the moon enters the umbra until it leaves, will be jointly provided by the Hong Kong Observatory and the Hong Kong Space Museum on the following web page from: www.weather.gov.hk/gts/hksm/astrophoto.htm (Please refer to figure 1 of attachment for relevant QR code).

Additionally, the Hong Kong Space Museum will organise an observation activity titled the "Night of Total Lunar Eclipse", in the central section of the Avenue of Stars in Tsim Sha Tsui from 7.30pm to 11.30pm.

"The public will have the opportunity to observe the total lunar eclipse with telescopes and various kinds of astronomical instruments under the guidance of Space Museum staff. The activity is provided free of charge and no registration is required," said the Curator of the Space Museum, Mr Chan Ki-hung.

Please refer to attached diagram for details of the moon's path during the eclipse. An animation of the lunar eclipse is also available on the Hong Kong Space Museum's YouTube channel (www.youtube.com/hkspacem/) (Please refer to figure 2 of attachment for relevant QR code).

Details of the lunar eclipse are as follows:
Hong Kong Time
Direction (Azimuth)
Elevation
Moon enters penumbra
7.32pm
East-northeast
(75 degrees)
26 degrees
Moon enters umbra
8.45pm
East
(79 degrees)
42 degrees
Total eclipse begins
10.06pm
East
(83 degrees)
60 degrees
Middle of eclipse
10.32pm
East
(84 degrees)
66 degrees
Total eclipse ends
10.58pm
East
(85 degrees)
72 degrees
Moon leaves umbra
0.18am (next morning)
Northeast
(52 degrees)
90 degrees
Moon leaves penumbra
1.32am (next morning)
West
(274 degrees)
74 degrees

Please refer to the Hong Kong Observatory website for an explanation of the cause and different stages of a lunar eclipse:
www.weather.gov.hk/gts/astron2011/lunar_eclipse_e.htm (Please refer to figure 3 of attachment for relevant QR code).

The next lunar eclipse potentially observable in Hong Kong will occur on June 4, 2012, which will be a partial eclipse. Also in 2012, an annular solar eclipse will be potentially observable in Hong Kong on May 21, and a transit of Venus on June 6. Both are rare astronomical phenomena.