Meteor over NZ 'a decent-sized rock'
Last night's meteor not only put on a visual show - it appears to have also shaken the ground, a seismologist says.
GNS duty seismologist Lara Bland said there was a small signal on two local seismographs that coincided with the timing of the meteor.
"From about 9:59:18 we recorded a small increase in higher frequency energy, for a duration of about 14-15 seconds," she said.
"I think it is fair to attribute this to the meteor."
The meteor was seen and heard by hundreds of people across the North Island. It likely exploded 20 to 30 kilometres above the earth, Astronomer Dr Grant Christie said.
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READ MORE: 'Definitely not lightning'
Christie, from the Stardome Observatory in One Tree Hill saw the meteor as he drove home at 10pm on Wednesday.
"It was a very very bright flash covering most of the sky," he said.
It appeared to have detonated at sea 150 kilometres east of Auckland and between 20 and 30 kilometres above the earth, Christie said.
Based on the energy it had released, it was probably between one and two metres across.
"It has the hallmarks of a decent-sized rock. If had been over Auckland it would have rattled the whole city."
The meteor was travelling very fast, about 20 or 30 kilometres a second.
"That's 20 or 30 times the speed of a high velocity bullet. So if you see it for five seconds, it's already gone 200 kilometres."
While it appeared close, a gap of about five minutes between the flash and sonic boom showed it was "hundreds of kilometres" away from observers in New Zealand.
The meteor was comparable to one which exploded 37km over Taranaki in 1999, Christie said.
Last night's event was seen and heard by hundreds of people.
Descriptions of the light ranged from white and orange to green and blue.
Peter Chisholm, driving home from Nelson heading north on SH6, said it was a double cone shape, "with the front end glowing Palmolive-dishwash green and the second end yellow, not dissimilar to the flames from a [rocket] engine".
The official twitter page for Auckland Civil Defence & Emergency Management said it was "definitely not lightning, most likely a #meteor".
TV presenter John Campbell tweeted: "Something fast and bright just briefly illuminated the sky west of Auckland. Zipped across the blackness. Extraordinary."
Jean Forbes in South Auckland said after seeing the bright light her doors shook.
In Papamoa Carl Denton said he and saw a bright flash and "a flaming asteroid heading towards the sea".
"It only lasted a few seconds but it really lit up the sky looked amazing."
In Hamilton Sam McCreary said: "I was standing outside my place in Hamilton at roughly 10pm and saw what I thought was an explosion in the sky. Looked like a big fireball."
Near Upper Hutt, Andy Wardle said he saw a "green fireball-type light heading in the straight down direction".
It "appeared to explode and split into three distinctive pieces".
"I believe this would have landed somewhere out in the Tasman Sea. It may have been a meteor or even perhaps a piece of space junk burning up," he said.
Retired Auckland University lecturer and meteorite expert Dr Joel Schiff said witness accounts pointed to a piece of stone or metal-like debris entering the Earth's atmosphere.
"If it's seen in various parts of the country it is most likely an object breaking up and burning up as it passes through our atmosphere," he said. "There would also be a sound from possible explosions as the debris enters the lower atmosphere."
In Nelson, Jessica Eynon said she "saw the sky flash white".
"I thought it was strange because unlike lightning only the sky flashed white and it did not light up my surroundings. It was one if the most beautiful moments of my life."
METEOR OR METEORITE?
Meteoroid: A meteoroid is a small rock or particle of debris that travels through space. They range in size from dust to about 10 metres in diameter.
Meteor: A meteor, also known as a shooting star, is a meteoroid that burns up as it passes through the Earth's atmosphere.
Meteorite: A meteorite is a meteoroid that survives falling through the earth's atmosphere and colliding with the earth' surface.
Comet: A comet is a bass of frozen gases, rock and dust that orbits the sun. When a comet is close enough to the sun it displays a visible coma, or fuzzy outline due to solar radiation, and sometimes a tail. Comets are about the size of a small town.
Asteroid: Asteroids are small solar system bodies that orbit the sun, usually in a belt between Mars and Jupiter. They are made of rock and metal, and can contain organic compounds. Asteroids are similar to comets but do not have the visible coma. They range in width from less than a metre to hundreds of kilometres.