Even by the usual standards of stargazing, it is a rare opportunity.
But anyone studying the horizon just after sunset in the coming days is in with a chance of spotting a comet last seen when Neanderthals walked the Earth, experts say.
First identified by astronomers last year, Comet C/2023 A3 (Tsuchinshan-Atlas) is thought to orbit the sun every 80,000 years or so.
It is thought to have originated from the Oort cloud, a giant spherical icy shell that surrounds our solar system and dates back 4.5billion years.
It made a close approach to our sun at the end of last month, travelling at more than 40 miles per second.
Comet C/2023 A3 (Tsuchinshan-Atlas) was last seen when Neanderthals walked the Earth, experts say
Dr Gregory Brown, senior public astronomy officer at the Royal Observatory Greenwich (pictured), said: The comet itself comes from an extremely distant part of our solar system
Now, though, it is set to make its closest approach to Earth, giving stargazers in the UK a good chance of spotting it in the evening - even without the help of binoculars or a telescope.
Dr Gregory Brown, senior public astronomy officer at the Royal Observatory Greenwich, said: The comet itself comes from an extremely distant part of our solar system, a place called the Oort cloud.
It contains lots of bits left over from the formation of the solar system. Every so often, one of those bits will be nudged inwards in towards the solar system, where it could end up in a very, very long orbit.
Those orbits can take extraordinarily long periods of time - thousands of years. The estimate on this particular comet is that if it is in a stable orbit, its last path to the inner solar system was about 80,000 years ago.
While comets often appear as a flaming fireball in the sky, Dr Brown said they are sometimes referred to as dirty snowballs, as they contain a considerable amount of ice.
As they fall in towards the sun they thaw out, and the gas and dust trapped within their ice is released, forming a misty cloud around them and the illusion of a tail.
In the last few weeks, the comet has appeared so close to the sun as it rises in the sky that it has been almost impossible to see from the UK.
But it has now passed around the other side of the sun, making it visible in the early evening instead.
Dr Brown said: At the moment, the comet is remarkably bright, which makes it unusual. Its a naked eye comet, so you dont need any additional things in order to be able to see it.
The tricky bit is working out when its going to be far enough away from the sun in the sky that we can see it, but not so faint by that time that its difficult for us to see.
He said it should hopefully become fairly visible in the sky by Tuesday, when it should be extremely bright compared to other comets that have passed by Earth.
Dr Robert Massey, deputy executive director of the Royal Astronomical Society, said the large, icy body could become the most impressive comet of the year.
Dr Massey said: Were all really excited about the prospect of the Comet A3 and how it might just be a nice bright object in the night sky.
I would think that youre going to need a pair of binoculars to pick it out, or a telescope - but who knows? It might be visible to the naked eye as well.
He said it is unlikely that the comet will be as easy to see as the Covid comet NEOWISE, which was visible in the evening skies throughout July 2020 and appeared as bright as the North Star, or the Hale-Bopp comet in the late 1990s.