A mountain-sized comet is expected to pass by Mars in an astronomical 'near miss' that'll see the huge object fly by the planet at a distance of just 87,000 miles. The event is so rare that astronomers are describing this as a 'once in a million years' event.
Named Siding Spring the huge comet is believed to have originated from an area of space known as the Oort Cloud. Found on the outer regions of our solar system the comet will be the first of its kind to be studied by astronomers and scientists.
As you'd expect all of Mars' rovers including Curiosity are being repositioned to make sure their cameras can capture the comet as it passes by.
Now 87,000 miles may not sound like that much of a near miss but in astronomical terms it's extremely close. To put it into perspective if the comet was passing by Earth it would be one third of the distance the Moon currently is from the from Earth.
Sadly when the comet passes by this weekend it'll only be those in the southern hemisphere who are going to be able to see it, instead we'll be relying on NASA's collection of satellites and observatories, all of which will have their eyes trained on the once in a lifetime event.