The European Space Agency (ESA) has christened it a "Christmas asteroid" but its real name is 2015 RN35 and it's a Pyramid of Giza-sized space rock about to hurtle past Earth.
The agency says it will pass by the planet at a safe distance — just close enough for Earthlings to get a glimpse.
Because it's coming so close to our home, 2015 RN35 is considered a Near-Earth Object (NEO) or a space object with the potential to hit Earth.
Here's what you need to know.
How big is 2015 RN35?
Between 60 and 140 metres across, according to the ESA.
But the agency concedes that there's actually not much known about the asteroid.
"We don't know what it’s made of or precisely how big it is or if it’s spinning on its axis or even know its orbit particularly well," the agency said in a statement.
"While we've found nearly all of the huge planet-killers, most of these middle-sized asteroids – of which there are several hundred thousand, and which could do great damage to a local area if they were to impact – are yet to be discovered."
The mystery surrounding the asteroid has prompted the ESA to turn to the public for photos that could lead to better understanding of the object.
How close will 2015 RN35 get to Earth?
At its closest approach distance, 2015 RN35 will be 679,800 kilometres from earth or 1.8 trips to the moon away.
In 2023, only two asteroids are predicted to get that close to Earth – 2020 DG4 in February and 2012 GD in June.
How do I see 2015 RN35?
Good news for us Down Under, 2015 RN35 will be most visible in the Southern Hemisphere.
But the catch is, because the asteroid isn't very bright, you will need a telescope 30cm or larger to view it.
The exact time of closest approach will be 6:10pm AEDT on Thursday, December 15.
While Thursday night will be the best time to catch a glimpse of the asteroid, you'll still be able to see it in the coming days.
It will have a visual magnitude below 14 from December 15 to 17 — for reference, Pluto has a visual magnitude of 14.
Why is it important to keep track of NEOs?
There are currently more than 600,000 known asteroids in our solar system but only around 20,000 of them are classed as NEOs, which depending on their size, could produce considerable damage.
Which is why it's so important for astronomers to keep track of where these rocks so scientists can develop planetary defences, like with NASA's recent successful DART mission.
ESA has created and released an asteroid toolkit with resources to make it easier for amateur astronomers to plan observations and help defend the planet.
"We use these tools every day to plan our observations, to visualise asteroid close approaches and to help us understand and explain the varied asteroid populations in the Solar System and the risk we face," explains Juan-Luis Cano, Information System Manager at ESA’s NEO Coordination Centre.
"We want them to be as useful to the rest of the world as they are to us, because planetary defence is a global effort."
