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Days after a massive fireball flashed through New Zealand’s skies last month, Steve Wyn-Harris spotted a small, black stone on the bare ground. The citizen astronomer was on the hunt for debris from the meteor that had flown over the North Island. He bagged the rock but wasn’t too confident, as he says most finds turn out to be “meteor-wrongs”.
But when he held the thumb-sized rock next to a fridge magnet, to detect iron and nickel in meteorites, it clicked. Wyn-Harris did the test on a video call with other citizen scientists and geologists and after the click “we were all yelling”.
“I went from doubting Thomas to a convert,” says Wyn-Harris.
His discovery marks the 11th confirmed meteorite to be found in New Zealand. Meteorites are the leftover rock that hits the ground after the meteor has burned up entering Earth’s atmosphere. Finding the debris in New Zealand can be difficult, a consequence of the country’s sparsely populated, rugged terrain.
Wyn-Harris is the director of Fireballs Aotearoa, an alliance of astronomers, geologists and citizen scientists that now has a network of 200 cameras set up around the country designed to help document meteor showers and recover meteorites.
On 28 July, the group and their cameras had tracked a meteor over the North Island, and people had rushed online to describe the dazzling display and a “huge boom”.
Footage indicated there was an exciting possibility of many fragments from the meteor on the ground. After crunching data, including wind speed and flight path projections, the group zeroed in on an area where they calculated meteorites could be strewn. They kept the location a secret, worried a public appeal for help could trigger a “meteor rush” – a martian meteorite found in Niger sold for more than $5m last year – though New Zealand law prohibits such sales.
Wyn-Harris says he found the meteorite near a riverbank while scouting farmland a day before he and the group were due to search the area.
“I wasn’t so excited when I first spotted and bagged it because I’d only been looking around … for 40 minutes,” he says.
But on the video call later that night a geologist looked at the rock and noted its crust had a meteorite quality. The next day, a team of 11 people carried out a wider search of the area.
Two days after Wyn-Harris’s discovery, which weighed eight grams, Liam McGovern, a geology PhD student, found a second fragment, weighing 39 grams. Over 10 days, the search party discovered four pieces, weighing 75g in total, including a fragment that had crashed on to the driveway of a house.
Wyn-Harris says the meteor’s trajectory before it entered the atmosphere indicated it came from the asteroid belt, making it an “ordinary chondrite”. The name is “unfortunate, because they’re not ordinary,” he says.
All four fragments will now be analysed further by Dr Marshall Palmer, a geologist who is part of Fireballs Aotearoa. Palmer will give the meteorites an official name and, together, they will become New Zealand’s 11th documented meteorite.
Prof James Scott, a geoscientist and the founder of Fireballs Aotearoa, says the pieces are “100%” meteorite, and he believes they likely share origins with New Zealand’s first meteorite discovered in 1863 nearby in Masterton.
“Both likely come from the same parent body, which was an asteroid from near the start of the solar system. That blows my mind. We have two rocks, formed elsewhere in space from a smallish asteroid … that has been catastrophically destroyed, and yet they land within 10km of each other.”
