
A ‘once in a lifetime double comet’ is expected to be visible from today as it comes into close proximity with Earth.
Now is your chance to view the cosmetic spectacle as from tonight (October 20) and the next few nights that follow, two comets will be visible in the night sky.
Swan and Lemmon will both make their appearances, which will coincide with the Orionids meteor shower, which is when debris falling from Halley’s Comet results in a shower of shooting stars.
According to NASA, Lemmon orbits the sun once every 1,351 years while Swan completes its orbit in 642, meaning it will be a once in a lifetime event to spot them.
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Swan will reach the peak of its visibility tomorrow but Lemmon will hang around a bit longer, with experts predicting that you can still spot it until November 2.
So, where in the world do you need to be to spot the comets? Swan will reportedly be located just above the southwestern horizon while Lemmon will be northwest.

Speaking to Metro, Finn Burridge, who is a science communicator at the Royal Observatory Greenwich, said: “Additionally, it is going to appear quite near the Sun, only visible right after sunset if at all, so you’d need some pretty good binoculars and very dark skies to get a glimpse.
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“But Lemmon is slightly brighter and will appear near Ursa Major (The Plough), which makes viewing it much easier.”
Meanwhile Stu Ashley, a stargazer who runs the UK Astronomy Facebook group, added: “Comets change rapidly and it’s almost impossible to predict.
“The term being floated around the astro community is ‘they should potentially become’. Now that’s pretty loose in terms of a promise.
“I’d exercise caution and promote the use of binoculars to guarantee sightings and a much better learning experience at a low cost.”
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Burridge went on to say: “Comets that make close approaches to the solar system are fairly rare; we only discover a handful a year that come close enough to the Earth to be visible without telescopes.
“So it’s certainly a rare and fortunate event to have two in one month!”
Ashley said: “But the fact they are both at their brightest (magnification) and that this coincides with a new Moon (super dark skies) makes it for me, an incredibly special event.”
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So, don’t hang around if you want to catch a glimpse of these two comets because they won’t be here again for a very long time!