Finding Meteorite Nqweba — the case of a curious child, a warm stone and a piece of tinfoil

The fragment of the meteorite that was provisionally named Nqweba after the town where it was found. (Photo: Deon Ferreira)

By Estelle Ellis

3 Sep 2024

South African scientists explained on Tuesday how they were in a mad dash – which was a feat in itself, they say, because geologists typically move slowly – to find fragments scattered on Earth when a meteorite exploded over the Eastern Cape on 25 August.

When nine-year-old Eli-zé du Toit saw a small stone drop from the sky while sitting on her grandparents’ porch in Nqweba (formerly Kirkwood), she went to investigate.

“I was busy playing with my dogs on my Oupa’s farm,” she said. “Suddenly, I just heard something like thunder. I saw a stone fall from the sky. I went to pick it up, and it was still warm,” she said.

meteorite eastern cape Nine-year-old Eli-zé du Toit with the team of scientists who are now studying the meteorite fragment she found. From left: Professor Roger Gibson (Wits), Dr Deon van Niekerk (Rhodes), Dr Leo Vonopartis (Wits) and Dr Carla Dodd (NMU). (Photo: Deon Ferreira)

“I went to show my Ouma. She said it was just a stone that fell from the sky. When my mommy came, she googled it and said, ‘I think it might be a meteorite,’” said Eli-zé.

A little while earlier, residents in Gqeberha, Nqweba, Cape St Francis, Patensie, Thornhill and other Eastern Cape towns had seen flashes in the sky, heard a thunderous boom and, in some places, felt an earth tremor.

The next day, Eli-zé’s mother, Jess, contacted Dr Carla Dodd at Nelson Mandela University. At the time of the meteorite event, Dodd was cycling around the Elands River.

“We heard the sound, and I thought, what was that? We thought maybe it was thunder, maybe it was an earth tremor.”

Dodd said they were grateful for Eli-zé’s find.

“Without that fragment, we had very little to go on,” said Dodd on Tuesday. Soon after she received the fragment, she was joined by a team from Wits and Rhodes universities in a search for more fragments.

Team gets working

meteorite eastern cape van niekerk Dr Deon van Niekerk from Rhodes University, who has been awarded the permit for the safekeeping and study of the precious meteorite fragments, explains what they have found so far. (Photo: Deon Ferreira)

The team has provisionally named the meteorite Nqweba — and it has been carefully preserved in tinfoil and plastic.

As Dr Deon van Niekerk from Rhodes University explained, their precious meteorite fragment “is not happy on Earth” and would start to rust if exposed to the elements.

“It is illegal to collect or handle these fragments without a permit [from the South African Heritage Agency],” he said.

People who had found fragments of the meteorite “must please contact us so we can take steps to preserve these fragments”.

Read more: Big bangs and sky stones — SA’s meteorite hunters on exactly what that flash in the sky was

“We have received hundreds of reports from people who saw or heard something,” said Dodd. “But in some cases,” she remarked, it was “meteo-wrong rather than meteorite” as people brought animal dung and ordinary stones for them to look at.

“We like to move more slowly as geologists,” Dodd laughed, describing their hectic time in the field.

Who saw it?

Reports of bright flashes as the meteor entered Earth’s atmosphere were received from the Garden Route, the Sunshine Coast, the Langkloof in the Eastern Cape, Gqeberha and even as far as Petrusburg in the Free State and the top of a mountain in Ceres.

When a meteor enters the atmosphere it explodes and the fragments are called meteorites.

Rhodes University’s Van Niekerk obtained a permit from the Eastern Cape Provincial Heritage Resources Authority to recover the meteorite fragments for scientific analysis.

meteorite eastern cape Vonopartis Dr Leon Vonopartis from Wits University removes the meteorite fragment from a protective container. (Photo: Deon Ferreira)

“Our response time was going to be critical if we were going to collect valuable scientific data and meteorite fragments, as well as to explain to the local public that this was a natural event and how the individual parts linked together,” said Professor Roger Gibson of Wits University.

He said that while they initially thought the meteor could have been as big as a car, they had adjusted their estimate — the meteor was probably the size of a motorcycle.

“But we hope it was bigger. Geologists always hope stones are bigger,” he said.

He said the team of researchers had gathered data from several sources to confirm and describe the event.

The first main flare was seen at around 8.50am on 25 August. They received 150 witness accounts and Gibson encouraged people to “keep them coming”.

Next, earth vibrations were felt, and a loud sound like thunder was heard from George to Gqeberha. He said calculations done by team members indicate that the largest part of the meteor fell over the Groot Winterhoek mountains, which start north of Kariega and stretch into the Western Cape.

nqweba The fragment from the meteorite provisionally named Nqweba. (Photo: Deon Ferreira)

Gibson said an infrasound monitoring station in Boshof near Kimberley, set up to monitor missiles during the Cold War, recorded the sound of the explosion.

The Centre for Near Object Studies recorded the meteor’s speed at around 20km per second before it exploded into meteorite fragments. Gibson said the energy expended was equal to 92 tonnes of TNT exploding. However, this happened at an altitude of 38km.

Gibson said they had gathered seismic data of the tremors caused by the event.

“All of this can be linked to a high-altitude bolide [a meteor that explodes in the atmosphere], but this was very high in the atmosphere,” he said.

What we know so far

“Events such as these are incredible and are very exciting,” said Dr Leonidas Vonopartis of Wits University.

The team of researchers has ascertained that the Nqweba Meteorite is achondritic, specifically a rare type within the howardite-eucrite-diogenite group.

The fragments have a dark black glassy coating (fusion crust) with a light grey interior, peppered with dark-green and light-green grains and clasts. Such meteorites provide valuable insights into the inner workings of other planetary bodies, offering scientists a glimpse into processes similar to those that formed Earth’s rocks.

nqweba The meteorite fragment. (Photo: Deon Ferreira)

“It is really cool to be able to study these rocks,” said Van Niekerk. He said they found five fragments weighing 90g in total. The fragments are similar to those previously matched to the asteroid 4Vesta, located in the asteroid belt between Mars and Jupiter.

“It is incredible that someone was there to see these fragments fall. It is like finding a needle in a haystack,” said Van Niekerk.

In the coming weeks, a team of researchers and astronomers affiliated with the Astronomical Society of South Africa will collect data from official observatories, with eyewitness accounts, to piece together the details of the bolide event. They will also conduct extensive searches for further meteorite fragments over a wide area of rugged terrain.

Van Niekerk said they needed to have the name of the meteorite approved. DM

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Team gets working

Who saw it?

What we know so far