A meteor-like ball of light was seen travelling on Wellington sky, leaving what appeared to be a condensation trail as if the light came from an aircraft Monday night.

The sighting puzzled onlookers as common meteors do not leave trails like this one did. But an astronomy expert said extra bright meteors do leave trails, and they are called fireballs.

"Fireballs happen on average about once a day around the world, but it's just rare to be in the right place at the right time... They would so often appear in isolated areas away from cities, or at 3am when everyone is sleeping, so we were very lucky to get to see such a sight," Carter Observatory programme manager John Field told Dominion Post.

As the trail seemed mysterious to non-scientists, police received over 20 calls - mainly from Wellington, Kaikoura and Otaki - around 7 o'clock in the evening from people who were concerned about the peculiar sight, Dominion Post reported.

Aside from Wellington, the bright fireball was also seen in the lower North Island, Blenheim and Christchurch at about 6:30pm.

Mr Field further explained the positioning of the sun at the time made the meteor look a lot brighter.

"It was high up so was catching the light from the setting sun, which made it easily visible for so many people... It was a fantastic combination of elements that came together to put on quite a show," he said.