In an extremely rare sight, that won't be bettered for 107 years in evening skies, the two brightest star-like objects in the sky will pass very close to one another. They are the planets Venus and Jupiter.
Closest approach is on Tuesday night (June 30).
"You do not need telescopes to see this 'Double Planet' but we will be able to show the disks of both worlds in the same field of view, something I have never seen in a lifetime's viewing!" said David Moore Editor of Astronomy Ireland magazine.
The two planets will be spectacularly close all week, with Monday, Tuesday and Wednesday being the best, and Tuesday night is the very closest.
"We expect this to be the most spectacular sight of the year, even better than the solar eclipse seen in March, and the total eclipse of the Moon due in September, so we are urging everyone to look in the West after sunset and tell us what they see?"said Mr Moore.
"As these are the brightest objects in the night sky, after the Moon, this event can be seen with the naked eye from anywhere in Ireland, so we want everyone to witness this rare, spectacular, and beautiful sight in nature!" said David Moore.