However, it was not a UFO as some thought, with it most likely to be a space rocket launched by China.
The clearest shots show that there were plumes of smoke coming out beneath the object.
“Did anyone see or get vision of some strange lights over Australia about an hour ago?” Astrophysicist Brad Tucker asked on Twitter.
Mohit on Twitter: "Saw this moving object around an hour back in the night sky..definitely not a plane or a drone. Suddenly it disappeared in the sky. #Unreal #SydneySky #UFO https://t.co/Swvw0WuYI0" / Twitter
“It looks like it was the plume (essentially exhaust) from a rocket.
“China launched a Long March 3B around that time. We might have seen the plume from it.”
China has been launching rockets to construct a new space station.