Supermoon tonight will be biggest and brightest full moon of 2023 so far

July full moon peaks just before midnight on Tuesday, but will appear full for one day either side

The first of four so-called ‘supermoons’ in a row will rise on Tuesday evening, offering skygazers the chance to see the biggest and brightest full moon of the year so far.

The Moon will be less than 365,000 kilometres (225,000 miles) from Earth, which is roughly 22,000km closer than usual.

Astronomers at Nasa posted details about the best way to witness the celestial phenomenon this week.

“The rising full Moon will be 3 degrees above the southeastern horizon,” the US space agency noted in a blog post.

“Tuesday afternoon, 4 July, 2023, at 6.26pm EDT (11.26pm BST), the Moon sill be at perigee, its closest to the Earth for this orbit.”

The term supermoon was first coined in 1979 as a way to describe any new or full Moon that is within 90 per cent of its closest approach to Earth, known as its perigee.

Their proximity to Earth makes them appear bigger and brighter compared to regular full moons, with this effect enhanced when the moon is closer to the horizon.

A phenomenon known as the ‘Moon Illusion’, with some scientists theorising that the Moon seems to be bigger when compared to the relative size of objects within our line of sight, such as buildings and trees.

However, astronauts have also observed the Moon Illusion aboard the International Space Station (ISS), even though they have no nearby objects to compare it to.

“Photographs prove that the Moon is the same width near the horizon as when it’s high in the sky, but that’s not what we perceive with our eyes,” a separate Nasa blog noted.

“Thus it’s an illusion rooted in the way our brains process visual information. Even though we’ve been observing it for thousands of years, there’s still not a satisfying scientific explanation for exactly why we see it.”