People across Wales will get their best opportunity to see a newly discovered comet in the sky this week offering what astronomers are calling a "once-in-a-lifetime" opportunity.

Comet Nishimura was discovered in August by Japanese astrophotographer Hideo Nishimura - who it was also named after.

The astrophotographer recorded Comet C/2023 PI when he was taking long-exposure photographs of the sky with a digital camera on August 11.

The newly discovered comet is already visible but tonight is set to present people with their best chance to see it with the naked eye.

When to see Comet Nishimura in the UK

According to Professor Brad Gibson, director of the E A Milne Centre for Astrophysics at the University of Hull, the comet is already visible to the naked eye.

Professor Gibson said the best time to see the comet was in the hour after sunset and the hour before dawn by looking east-north-east, towards the crescent moon and Venus.

But added Tuesday (September 12) would present people with their best chance to see the newly discovered Comet Nishimura. 

Professor Gibson said: “The comet takes 500 years to orbit the solar system, Earth takes one year, and the outer planets can take many decades.

“Halley’s Comet, which caused much interest during its last nearby visit to Earth in 1986, takes 76 years to orbit the solar system.

“So, to say this is a once-in-a-lifetime opportunity to see Nishimura isn’t an exaggeration.”

Prof Gibson added: “It can already be seen but it will be 78 million miles from Earth on September 12 and that should be the best chance to see it with the naked eye.

“On average, people have the chance to see such a naked eye comet once a decade – this is a rare and exciting opportunity.”

This may be the only chance stargazers get to catch a glimpse of Comet Nishimura.

Prof Gibson said it will pass closest to the sun on September 17, when it will be just 27 million miles away.

He said there is a real chance it may not survive this close fly-by.

How to get the best view of Comet Nishimura

According to South Wales Argus astronomy writer Jonathan Powell "you will need to be up early in the morning with a good view of the eastern horizon".

Mr Powell said: "To get the best possible views of Comet Nishimura you will need to be up early in the morning with a good view of the eastern horizon, as unhindered as much as possible by artificial lighting.

"Several hours before dawn and using the chart, sweep the area of the comet’s predicted path, firstly with binoculars to try and pinpoint its whereabouts.

"It will prove a challenge to spot even at naked eye and will be little more than a fuzzy blob, but ‘fuzzy blob’ or not, it’s a comet in our skies!"

To track the comet you can visit The Sky Live website.

Will I be able to see Comet Nishimura? The forecast for Tuesday, September 12

Clear weather conditions will help improve your chance of catching a glimpse of the once-in-a-lifetime comet.

To see if you're in luck and will be blessed with clear skies to see Comet Nishimura, we've rounded up the predicted forecast for tonight across Wales - from BBC Weather - to see the best locations to take advantage of this "rare and exciting opportunity".

Wrexham: Light rain and a gentle breeze (16C)

Flint: Light rain showers and a gentle breeze (17C)

Conwy: Light rain and a moderate breeze (16C)

Newtown: Light rain and a gentle breeze (17C)

Newport: Light rain and a gentle breeze (19C)

Cwmbran: Light rain and a gentle breeze (19C)

Cardiff: Light rain and a gentle breeze (20C)

Swansea: Light rain and a gentle breeze (19C)

Haverfordwest: Sunny intervals and a moderate breeze (17C)