A conjunction or a 'meeting in the sky' is a rare phenomenon where two or more astronomical objects appear close together in the sky.
The exciting event is due to happen on Tuesday 13 July when Mars and Venus will appear to move towards one another.
Astronomical conjunctions can happen with any planet, star or moon - it varies depending on the changing planetary alignments.
Although planets in a conjunction often seem close together, this is actually an illusion. In fact, planets during conjunctions remain millions of kilometres apart and simply occupy the same space in the night's sky.
Conjunctions with the moon happen frequently because the moon moves around the earth so quickly - planet conjunctions, however - are far more rare.
Planets move slower in the sky, and so planetary conjunctions are not so frequent - for instance a meeting of Jupiter and Saturn will happen roughly once every 20 years.
Will the Venus and Mars conjunction be visible from the UK?
Mars and Venus are our closest planetary neighbours here on earth, but that doesn't mean they'll be easy to spot on 13 July.
The angular seperation between Mars and Venus will be very small this time, so they will likely appear as one mass in the night's sky.
On the 13th July, Mars has been classified as 'slightly difficult to see', whereas Venus has been deemed to be in 'fairly good visibility'.
In order to spot the hard-to-see conjunction, try looking to the western horizon just as it's getting dark - at around 19.15pm during mid-July.
The rare phenomenon should be visible with the naked eye, which is great news for those back-garden star-gazers.
Both Venus and Mars are expected to move gradually further away after the 13th.
