Stargazers are in for a treat tonight, as Jupiter and Venus will be not be seen closer together for another 40 years.
The two planets will appear low in the west after sunset and you will not be able to see them so close together again until 2065.
Astronomy Ireland is setting up powerful telescopes in Roundwood, Co. Wicklow, to give people an unrivalled view of the planets.
It's part of their Star-b-que which will also feature talks, demonstrations and food.
David Moore from Astronomy Ireland has this advice: "Try to look low down just where the sun sets.
"Just to the left of that point, you will pick up Venus, but Jupiter will be so close that we are not sure the naked eye will be able to separate the two, you may actually need a pair of binoculars.
"Normally Jupiter is very bright and easy to see, but it will be so close to Venus that you might not be able to split them, they are that close together."