A meteorite recovered in the Wairarapa after a spectacular fireball streaked across the lower North Island has become New Zealand’s 11th confirmed meteorite — and only the fourth ever recovered after its fall was witnessed.
The rock entered Earth’s atmosphere at 10.26pm on July 28, and could be seen lighting up the skies from Kāpiti to Masterton before breaking apart.
Many people also reported hearing sonic booms moments later. A resident in East Taratahi, Wairarapa describing hearing “multiple crackles, several distinct booms and prolonged rolling rumbling, giving the impression of an object travelling through the atmosphere and fragmenting repeatedly".
The fireball was captured by Fireballs Aotearoa’s nationwide network of meteor cameras, which allowed scientists to calculate where surviving fragments were likely to have landed.
After several days searching farmland north of Masterton, four meteorite fragments weighing 8g, 9g, 12g and 40g were recovered by scientists from Fireballs Aotearoa.
Victoria University of Wellington PhD student Liam McGovern was among those searching and located the largest meteorite fragment, describing his discovery as "pure shock and enjoyment".
“I was shaking afterwards, because I’ve spent the last six years of my life studying these rocks," McGovern told 1News.
"From a laboratory perspective I’ve handled a lot of meteorites before, but actually going and collecting one was really unreal.”
The meteorite would now be formally classified before receiving an official name as New Zealand’s 11th documented meteorite.
Victoria University geochemistry laboratory manager Bruce Charlier joined the search alongside McGovern and other scientists, and said recoveries like this were exceptionally rare in New Zealand.
“There’s now been 11 confirmed meteorites in total, but there’s a difference between a find and a fall,” he explained.
“A find is something that’s lain on the ground for hundreds or even thousands of years, whereas a fall is something that’s actually observed to fall and then collected straight away. There’s only been four of those in New Zealand.”
Despite several bright fireballs being spotted over New Zealand skies in recent weeks, Charlier said that did not mean more meteorites were entering the Earth’s atmosphere.
Instead, he said advances in New Zealand's meteor detection technology meant more were being recorded and tracked than in the past.
"We’re really good at spotting them now,” he said. "If there’s something inbound, we’re very likely going to see it."
Ancient rock from dawn of Solar System
Fireballs Aotearoa director Steve Wyn-Harris said the meteor was first detected about 90km above Earth, travelling at around 14km per second.
"This speed represents what it has been travelling at for millions of years around the Sun," he explained.
Wyn-Harris said as it descended and passed through the atmosphere, air compressed and heated around the rock, melting its outer layer and creating the bright fireball which was seen across the lower North Island.
Professor James Scott of Fireballs Aotearoa said the trajectory which the rock followed prior to entering the atmosphere indicated that it was derived from the asteroid belt between Mars and Jupiter, where millions of rocky objects orbited the Sun.
"The rock is therefore certainly from the start of the Solar System and almost 4.6 billion years old," Scott said.
Charlier added that meteorites were usually made recognisable by a distinctive black “fusion crust” formed as they travelled through Earth’s atmosphere.
"The interior is very light coloured, but the exterior usually has this very diagnostic fusion crust, which is usually black or very dark,” he said.
He said anyone who found a dark rock that looked out of place should have it checked by an expert to see if it was a meteorite.
“If you think you’ve got something that is out of the ordinary, and it has this black fusion crust, then I would definitely seek an expert opinion on it."
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