NASA on Thursday announced that two massive space objects are hurtling towards Earth- one may be a comet and the other is still not clear, it may be an asteroid.
The event will be witnessed by the end of this week but the mystery object isn't expected to make an appearance until February.
Talking about details, NASA dubbed the object as "2016 WF9" and was detected by NASA's asteroid- and comet-hunting NEOWISE project on 27 November 2016.
The object is roughly 0.3 to 0.6 miles (0.5 to 1 kilometres) across and has been travelling across the solar system.
It has been travelling around for 4.9 Earth-years, passing under the main asteroid belt and then Earth's own orbit.
Then it will head back towards the outer solar system. However, NASA is unclear whether it is a comet or asteroid.
Deputy Principal Investigator James "Gerbs" Bauer at NASA's JPL says, "2016 WF9 could have cometary origins. This object illustrates that the boundary between asteroids and comets is a blurry one; perhaps over time this object has lost the majority of the volatiles that linger on or just under its surface."NASA says that the mysterious 2016 WF9 is dark like a comet and appears to lack the characteristic dust and gas cloud that defines a comet.