STAR GAZERS will gather in Phoenix Park tonight to train their telescopes on the ultimate in celestial activity, a total eclipse of the moon.
Clear skies are forecast when the moon moves into the Earth's shadow from around 10 p.m. until 3a.m.
At the same time, the comet Hyakutake will be clearly visible in the north west sky. The comet is fading, but the two hours of darkness during the lunar eclipse will make it easier to see.
Up to 1,000 people are expected to attend the National Eclipse and Comet Watch, organised by Astronomy Ireland, in the car park at the Papal Cross. They will be able to view the eclipse through powerful telescopes.
Astronomy Ireland's chairman, Mr David Moore, is predicting that the event will provide hours of "oohs and aahs" as the moon takes on a blood red, orange or copper glow. The reddening effect is caused by the sun's rays being bent by the Earth's atmosphere.
"You don't need telescopes to see the eclipse and you can see it from anywhere in the country, urban or rural," he said.
The eclipse will start at around 10 p.m., when the left edge of the moon will start to dim slightly as it enters the Earth's shadow. At 11.21 p.m., the moon will touch the Earth's shadow and slowly move across it until it is totally eclipsed at 12.24 a.m.
From this moment until 1.53 a.m., when the moon begins to emerge from the Earth's shadow, the sky will darken as the moon takes on a dim glow. It will fully emerge from the Earth's shadow at 2.59 a.m.
The sight of the moon "turning to blood" has long been viewed as a portent of doom.
In Biblical days, an eclipse was believed to have heralded the death of King Herod, while in ancient Japan, men would lie on the ground and howl like dogs to ward off its evil effects.