Stargazers will have the opportunity to spot Mercury, Jupiter, Venus, Uranus and Mars on the horizon.

The planets were visible in the West from around half an hour after sunset, according to Jake Foster, an astronomer at the Royal Observatory in Greenwich.

Venus, Jupiter and Mars will be "easily visible from the naked eye" even from a bright city like London, though a telescope may be needed to spot Mercury and Uranus, he told Sky News.

"If you face towards the western horizon, you should be able to see with the naked eye - so without any specialist equipment - three planets in a neat line across the sky, along with the moon.

"If you have a telescope or a pair of binoculars, possibly even five planets and the moon."

Tonight will be the best time to view the alignment.

Although the majority will still be visible over the coming nights, Jupiter will drop away.

Why does this happen?

The planetary alignment occurs because the solar system is shaped like a flat disc, with the planets orbiting the same flat region in space, Mr Foster said.

"So inevitably from time to time they will all come into alignment along this flat line that they follow across the sky," he explained.

"This can happen a few times a year. The amount of planets you can see changes, the order of the planets can change."

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When will it happen next?

In June, Mercury, Venus, Mars, Jupiter and Saturn could be seen in a line in the night sky.

The next alignment will happen in Autumn, featuring Mercury, Saturn, Venus, Uranus and Mars.

"We always encourage people to get out there and feel more connected to the skies above them," Mr Foster said.

"These events are a great chance to get outside and there are a few easy targets that you can see - the amazing planets of the solar system."