Tertius News is an AI-native newsroom: an AI model reads the linked source articles below and extracts what each outlet reported, so you can compare their coverage side by side. How this works →

Australian researchers date Earth’s oldest known asteroid impact

Researchers from Curtin University have dated an asteroid impact in Western Australia's Pilbara region to about three billion years ago, making it the oldest known impact crater on Earth. The team analysed zircon and apatite minerals to pinpoint the event.

By Tertius News AI Desk 2 outlets · 2 articles Version 1 Coverage Jun 23–24, 2026 Published Aug 15

Australian researchers date Earth's oldest known asteroid impact

The impact occurred during the Archean eon, a period 4 to 2.5 billion years ago, when tectonic plates were beginning to form and early life was emerging. The crater, known as the North Pole Dome, lies in the northeastern part of Western Australia's Pilbara region.

How the age was determined

The team, led by geologist Professor Chris Kirkland from Curtin's Timescales of Minerals Systems Group, analysed rare geological features called shatter cones, which form under the intense pressure of a meteorite impact. Using two separate methods, they dated minerals in the damaged rocks.

First, they examined tiny zircon grains that were recrystallised in the heat of the strike. These zircons forked into unusual skeletal patterns, a feature generally found only in impact craters on the moon. The age of these crystals was measured using an Australian-designed instrument called the Sensitive High-Resolution Ion MicroProbe, which determined that the shock occurred about 3 billion years ago.

Separately, the scientists analysed apatite, a calcium phosphate mineral that grew in the rock after the impact. According to co-author Dr. Simon Johnson, the discovery places the North Pole Dome structure as the planet's oldest known impact crater and "the only recognized example from the Archean eon."

Significance for understanding early Earth

Professor Kirkland described the well-preserved rock formations as an extremely rare and globally significant archive of geological time, offering "a rare glimpse of the violent processes that shaped the early Earth."

"There's very few places that are these deep time capsules that let us peer into the formative processes on our planet. That's why they're quite special," he said.

The findings reveal that the North Pole Dome crater is older than Yarrabubba, another crater in Western Australia, which was previously considered the oldest at 2.2 billion years old. The impact left a "mineral clock" behind, Kirkland explained: "By dating minerals that were remade or newly grown in the damaged rocks, we can now pin down when this extraordinary event happened."

How each outlet told it

The Guardian — World as of Jun 23, 2026, 10:30 PM UTC

Framing: Discovery of the world's oldest impact crater — Informative and enthusiastic

Facts Included:

A meteorite struck Earth three billion years ago
The impact left behind evidence of the world's oldest impact crater in Western Australia's Pilbara region
The crater is known as the North Pole Dome crater
Scientists from Curtin University analysed the age of rare geological features, called shatter cones
The researchers used two separate methods to determine when the meteorite strike occurred
The age of 'little lightning bolts' of zircon embedded in the basalt rock were analysed
The age of apatite, a calcium phosphate mineral, was also analysed

Read the source article →

TASS — English as of Jun 24, 2026, 2:00 PM UTC

Framing: Discovery of the Earth's oldest asteroid impact — Informative and objective

Facts Included:

Scientists from Australia's Curtin University have dated the Earth's oldest asteroid impact at three billion years old
The team investigated rock formations at the North Pole Dome in Western Australia
The findings helped identify the exact age of the impact structure

Read the source article →

What was claimed, and who backed it

Each row is one claim, attributed to the outlet whose wording states it most clearly. Confidence rates how directly the source text states the claim — explicit and unhedged rates high; hedged, pieced-together, or internally inconsistent statements rate lower. It does not measure whether the claim is true. Status counts the distinct outlets we found asserting it — so a single-source claim can still show high confidence, and a multi-source claim can show medium. Every one of those outlets is named beside the status, so you can check the count against the list. For claims extracted before we began storing that list, the row says so: it names the outlet the claim is quoted from and states that we have not recorded which outlets backed it. Outlets wrote at different times, so a figure that evolves — a casualty count, for example — can legitimately differ between rows; check the "as of" time next to each claim's source.

Claim	Confidence	Status
ClaimA meteorite struck Earth three billion years ago, leaving behind evidence of the world's oldest impact crater in Western Australia's Pilbara region.	ConfidenceHigh	StatusMulti-source quoted from The Guardian — World as of Jun 23, 2026, 10:30 PM UTC the outlets behind this status were not recorded for this claim
ClaimThe impact crater is known as the North Pole Dome crater.	ConfidenceHigh	StatusMulti-source quoted from The Guardian — World as of Jun 23, 2026, 10:30 PM UTC the outlets behind this status were not recorded for this claim
ClaimScientists from Curtin University analysed the age of rare geological features, called shatter cones, to determine when the meteorite strike occurred.	ConfidenceHigh	StatusSingle-source via The Guardian — World as of Jun 23, 2026, 10:30 PM UTC
ClaimThe researchers used two separate methods to determine when the meteorite strike occurred, including analysing the age of 'little lightning bolts' of zircon embedded in the basalt rock and the age of apatite, a calcium phosphate mineral.	ConfidenceHigh	StatusSingle-source via The Guardian — World as of Jun 23, 2026, 10:30 PM UTC
ClaimThe North Pole Dome crater is older than Yarrabubba, another crater in Western Australia, previously considered the oldest at 2.2 billion years old.	ConfidenceHigh	StatusSingle-source via The Guardian — World as of Jun 23, 2026, 10:30 PM UTC
ClaimEarth was a vastly different place at the time the meteorite hit, with few pieces of continental crust, a dimmer sun, and the moon closer, and early life present in the form of stromatolites.	ConfidenceHigh	StatusSingle-source via The Guardian — World as of Jun 23, 2026, 10:30 PM UTC
ClaimThe discovery of the North Pole Dome crater's age places it as the planet's oldest known impact crater and the only recognized example from the Archean eon.	ConfidenceHigh	StatusSingle-source via TASS — English as of Jun 24, 2026, 2:00 PM UTC

Transparency & Audit Trail

2 outlets · 2 articles consulted: The Guardian — World, TASS — English 7 claims extracted Version 1 Written 2026-08-15