An exhaustive examination of Northwest Africa (NWA) 16286, a lunar meteorite possessing a distinctive geochemical signature, furnishes novel perspectives on the evolutionary trajectory of the Moon’s internal structure, underscoring the protracted duration of its eruptive phenomena.
Backscattered electron image of the NWA 16286 sample. Image credit: Joshua Snape / University of Manchester.
Discovered in the African continent in 2023, NWA 16286 represents merely one of thirty-one basaltic rock samples of lunar origin officially cataloged on Earth.
The 311-gram extraterrestrial fragment’s unique composition, characterized by vitreous inclusions and interstitial veins, intimates that it likely underwent significant structural disruption due to the impact of an asteroid or meteorite on the lunar surface prior to its subsequent ejection and eventual terrestrial deposition.
The contemporary research conducted by scientists affiliated with the University of Manchester substantiates a hypothesis proposing that the Moon harbored enduring internal mechanisms for heat generation, which fueled its volcanic processes across multiple distinct epochs.
Isotopic analysis of lead isotopes has precisely dated the genesis of this geological specimen to approximately 2.35 billion years ago, a temporal interval from which exceptionally few lunar samples have been recovered, thus positioning it as the most recently formed basaltic lunar meteorite unearthed on our planet.
Its unusual geochemical profile distinguishes it markedly from materials obtained through prior lunar exploration initiatives, with chemical indicators suggesting an origin from magma that solidified subsequent to its ascent from profound depths within the Moon’s lithosphere.
“Lunar materials retrieved via sample return missions are invaluable for the insights they impart, yet their scope is confined to the immediate vicinities of those mission landing zones,” stated Dr. Joshua Snape from the University of Manchester.
“Conversely, lunar meteorites, through the erosive force of impact cratering, can potentially originate from any location across the Moon’s entire surface.”
“Consequently, a degree of serendipity surrounds this particular sample; its fortuitous descent to Earth has unveiled secrets of lunar geology without necessitating the formidable financial investment of a dedicated space expedition.”
Incorporating notably large crystals of the mineral olivine, this rock constitutes a variant of lunar volcanic basalt designated as olivine-phyric basalt. It exhibits moderate concentrations of titanium and elevated levels of potassium.
Beyond the remarkable age of the sample, the investigators identified that the isotopic composition of lead within the rock—a geochemical imprint preserved from its formation—indicates an origin from a subterranean lunar source characterized by an exceptionally high ratio of uranium to lead.
These chemical indicators may prove instrumental in delineating the processes that facilitated sustained periods of internal thermal generation on the Moon.
“The age of this sample is particularly significant as it bridges an approximately billion-year hiatus in the Moon’s volcanic chronology,” remarked Dr. Snape.
“It predates the basalts collected by the Apollo, Luna, and Chang’e 6 missions, yet is younger than the much more recent samples procured by China’s Chang’e 5 mission.”
“Its antiquity and compositional makeup demonstrate that volcanic activity persisted on the Moon throughout this extensive period, and our findings suggest a continuous internal heat-generating process, potentially driven by the decay of radiogenic elements over geological timescales.
“Lunar rocks are infrequent finds, making any sample that exhibits unique characteristics and deviates from the established norm of considerable scientific interest.”
“This specific specimen offers novel parameters for understanding the timing and mechanisms of lunar volcanic events.”
“Substantial knowledge gaps persist concerning the Moon’s geological history, and with further analytical efforts to precisely ascertain its surface origin, this rock will serve as a crucial guide for selecting optimal landing sites for forthcoming sample return missions.”
The research team disseminated their findings today at the Goldschmidt Conference 2025, held in Prague, Czech Republic.
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Joshua F. Snape et al. Northwest Africa 16286: investigating the age and origin of a new lunar mare basalt. Goldschmidt Conference 2025
