Daytime meteor sighting 'very unusual', says scientist

A meteor which shot across the skies above the lower North Island yesterday afternoon released about a seventh of the energy of the Hiroshima bomb, a space scientist says.

Duncan Steel, who was formerly with NASA, told Morning Report it was extremely unusual to see a meteor during the day.

In his own lifetime, he'd seen just one, some 40 years ago.

"I've seen many, many, many at night, but a daytime meteor - we call it a fireball because it's very bright - are very unusual."

He said the "extremely high-energy event" released the energy equivalent of about 1.8 kilotons of TNT.

"That's about one seventh of the Hiroshima bomb, therefore it was quite a blast but thankfully at the very high altitude - as we'd expect - so it didn't cause any damage except the people's nerves."

Steel said many of those who witnessed the meteor flashing through the sky just before 2pm yesterday believed it was closer than it actually was because they were likely comparing it to their experience of seeing commercial jetliners, which flew at an altitude of about 10 kilometres.

"[The meteor] was at 35 kilometres - the terminal height - so much higher, and because of that much further away from them," he said.

"People from Wellington thought it was just across the bay, no it wasn't, it was considerably further away than that, so a good distance away from the observers."

The natural phenomenon was quite an amazing thing to see, Steel added, though it would have been even more impressive by night.

"If that had been at night time it would've been lighting up the surrounds just like daylight."

Steel said after initially viewing dashcam video of the meteor he believed it was likely the size or a rugby ball or basketball, but data from American early-warning satellites showed it was in fact "much bigger and more energetic than that".