A visitor will be making a fast flyby of earth this Christmas Eve - Asteroid 2003 SD220.
Astronomer Ian Griffin, the director of the Otago Museum, said the best chance of seeing it for those with a telescope was about 2am.
Mr Griffin told Checkpoint that at its closest point to earth, the asteroid will be about 11 million kilometres away.
He said the asteroid is about one kilometre long and will be moving at five miles a second.
Mr Griffin said NASA was hoping to land a spaceship on the asteriod as it passes much closer to earth in the mid-2020s as part of its 'Orion' missions.