It's eyes to the skies tonight as we'll be able to see a super rare full blue moon, which only happens every couple of years.
Despite its name, the blue moon won't look blue; it'll look bright white. It happens when the moon is positioned on the opposite side of the Earth from the sun - meaning the moon will look especially illuminated.
Usually there are only three full moons in a season, but this time around there are four.
The blue moon only occurs every two-and-a-half years. Credit: PA
NASA explains: "A blue moon is special because it is the 'extra' moon in a season with four full moons. This usually only happens every two and a half years."
As you'd assume from the saying 'once in a blue moon', it's a pretty rare occurrence. We won't see another full blue moon until 22 August 2021.
Speaking to the Express, the Royal Observatory Greenwich explained: "Normally blue moons come only about every two or three years.
"In 2018 unusually, we had two blue moons in one year and only two months apart - and one was a lunar eclipse.
"The next time we will get two blue moons in a year is 2037."
For your best chance of seeing it in the UK, you'll need to pop outside at 10.11pm. If you're really keen on getting a decent view, then you'd be best trying to get out into an area with less light pollution.
Nasa also announced that there will be more astronomical events this weekend.
In a statement it said: "By the morning of the full moon on 18 May 2019, as morning twilight begins, Jupiter will appear in the south-southwest about 23 degrees above the horizon and Saturn will appear in the south about 30 degrees above the horizon.
"Venus will be rising about seven minutes after morning twilight begins but should be visible low in the east-northeast until about 30 minutes before sunrise. Mercury will not be visible, lost in the glow of the sun."
Featured Image Credit: PA