← No. 015 WED 14 OCT 2026

Farside Moon rocks show the magnetic field revived.

Chang’e‑6 basalts — Moon farside, South Pole–Aitken basin

Basalt fragments returned by China’s Chang’e‑6 mission from the Moon’s farside carry remanent magnetization set about 2.8 billion years ago. The signals indicate a field about a tenth to two‑fifths as strong as Earth’s today, implying the lunar dynamo had recovered after an earlier fade near 3.1 billion years ago. This first direct farside reading was reported on 19 December 2024.

Why it’s interesting

Fig. 015 Right‑hand concentric lunar time bands; the bold arc marks the ~2.8‑billion‑year rebound to about one‑tenth to two‑fifths of Earth’s field, recorded in farside basalts.

Why it’s interesting

It fills a missing chapter in the Moon’s story and shows a planetary dynamo can falter and rally. That possibility now feeds models of how rocky worlds sustain magnetic fields over deep time.

The longer version

The Moon once generated a global magnetic field that later waned. Until Chang’e‑6, the farside had no direct record. Basalt fragments returned from the South Pole–Aitken basin, dated to about 2.8 billion years ago, carry natural magnetization showing the field had strengthened again after a sharp decline around 3.1 billion years.

Researchers estimated intensities at roughly a tenth to two‑fifths of Earth’s present field using non‑thermal ARM/IRM methods and ran tests indicating the signals are primary; thermal checks would be a valuable follow‑up. Reported online on 19 December 2024 and assigned to Nature’s July 2025 issue, this is the first direct palaeomagnetic constraint from the lunar farside.

Edition: No. 015
Date: Wednesday 14 October 2026
Subject: Chang’e‑6 basalts
Locality: Moon farside, South Pole–Aitken basin
Period: about 2.8 billion years ago
Field: space
Evidence: 4 sources, 1 primary

See how we got here

Found after 22 research paths · Selected from 6 candidates

01 Lunar magnetism Apollo rocks showed the Moon once had a strong field.
02 Far‑side gap No direct paleomagnetic record from the farside existed.
03 Chang’e‑6 return First samples brought back from the lunar farside in 2024.
04 2.8‑Ga basalts Volcanic clasts formed about 2.8 billion years ago.
05 Non‑thermal estimates ARM/IRM methods yield about a tenth to two‑fifths of Earth’s field.
06 Dynamo rebound Field strengthened after a sharp decline near 3.1 Ga.
→ Farside Moon rocks show the magnetic field revived.

Sources

Nothing publishes without independent sources. How we verify →

1
A reinforced lunar dynamo recorded by Chang’e‑6 farside basalt
Nature · 2025 · peer reviewed Primary

Palaeointensities ~5–21 μT; first direct farside constraint; rebound after ~3.1 Ga; online publication date; assignment to 2025 volume.

doi.org
2
Lunar farside volcanism 2.8 billion years ago from Chang’e‑6 basalts
Nature · 2025 · peer reviewed

Independent confirmation that CE‑6 returned ~2.8‑Ga farside basalts.

nature.com
3
Magnetic signatures and origins of ferromagnetic minerals in Chang’e‑6 lunar farside soils
Nature Communications · 2025 · peer reviewed

Corroborates the ~5–21 μT range reported for CE‑6 basalts and notes the values come from non‑thermal paleointensity methods.

doi.org
4
Chang’e‑6 farside basalts reveal a reinforced lunar dynamo (press release via EurekAlert!)
Chinese Academy of Sciences · 2024 · scientific organization

Restates that CE‑6 basalts record ~5–21 μT and a resurgence of the lunar dynamo at ~2.8 Ga.

eurekalert.org

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