Armagh Observatory, 17 January 2000

Sky watchers will be treated to the first total lunar eclipse of the year on the morning of Friday, 21st January, weather permitting. A total lunar eclipse occurs when the Moon completely enters the dark shadow cast by the Earth. The Earth blocks the direct light of the Sun from reaching the Moon. However, the Earth's atmosphere can scatter some of the Sun's light, re-directing a portion of it towards the Moon. Thus the Moon does not usually go completely dark during a total lunar eclipse, but will usually turn a dark shade of red. The actual colour depends on how transparent or dusty the Earth's atmosphere is at the time.

The partial phase of the eclipse begins at 2:04 a.m., when the Moon enters the Earth's faint (penumbral) shadow. The most spectacular part of the eclipse, the total phase, lasts from 4:04 a.m. until 5:23 a.m. when the whole Moon is within the Earth's dark (umbral) shadow. The second partial phase of the eclipse ends at 7:23 a.m., when the final part of the Moon emerges from the Earth's penumbral shadow.


John McFarland at the Armagh Observatory Tel.: 028-3752-2928.

Last Revised: 18th January 2000
WWW contact:
Go to HOME Page