SKYWATCHERS ACROSS IRELAND are being urged to look west after sunset tonight as Venus and Jupiter will appear side-by-side in Irish skies.

The rare phenomenon, known as a conjunction, will see the two brightest planets in the night sky appear exceptionally close together, creating what astronomers have dubbed a ‘double planet’.

“This is the highlight of the year, and indeed for many years,” said Astronomy Ireland editor David Moore.

“You will be able to see Venus and Jupiter blazing at their closest in Irish skies from sunset on. No other conjunction can be this bright because these are the two brightest planets there are.”

Venus and Jupiter are both far brighter than any star visible in the night sky. According to Moore, the pair will appear so close together that they can be covered by a single finger held at arm’s length.

“You just don’t get a more impressive sight than that,” he said.

While the planets appear close together, the alignment is simply a line-of-sight effect.

Venus is actually around five times closer to Earth than Jupiter, while Jupiter itself is roughly 12 times wider than Venus.

The best viewing conditions are expected soon between 10pm and 11pm, shortly after sunset.

Although June’s bright twilight will slightly reduce the spectacle, both planets should still be clearly visible to the naked eye.

Astronomy Ireland is also encouraging people to photograph the event using their smartphones and submit their best images for publication.

The conjunction will remain visible for several nights Wednesday also offering particularly good viewing opportunities.

“At the very least watch every clear night over the next week and get the whole family out to witness such a bright and rare planet alignment,” Moore said.

“It will be something they will remember for the rest of their lives.”