New research shows that the Martian meteorite Northwest Africa (NWA) 7034, known more commonly as ‘Black Beauty,’ was ejected between 5 and 10 milliom years ago from a crater in the north-east of the Terra Cimmeria-Sirenum province in the southern hemisphere of Mars.
An artist’s impression of where an asteroid hit the surface of Mars 5-10 million years ago, ejected NWA 7034 and its transit to the Earth. Image credit: Curtin University.
NWA 7034, approximately 320 grams in weight, is a regolith breccia from Mars.
Known more commonly as ‘Black Beauty,’ it was discovered in the Moroccan Sahara desert back in 2011.
NWA 7034 contains the oldest Martian igneous material ever dated — about 4.5 billion years old.
“Black Beauty is the only brecciated Martian sample available on Earth, meaning it contains angular fragments of multiple rock types cemented together which is different from all other Martian meteorites that contain single rock types,” said Dr. Anthony Lagain, a researcher with the Space Science and Technology Centre at Curtin University.
“For the first time, we know the geological context of the only brecciated Martian sample available on Earth, 10 years before NASA’s Mars Sample Return mission is set to send back samples collected by the Perseverance rover currently exploring the Jezero crater.”
NWA 7034. Image credit: NASA.
Using a supercomputer at the Pawsey Supercomputing Research Centre, and the Curtin HIVE (Hub for Immersive Visualisation and eResearch), Dr. Lagain and colleagues analyzed a very large volume of high-resolution planetary images through a machine learning algorithm to detect impact craters.
They found that NWA 7034 belongs to the ejecta deposits of the Khujirt crater formed 1.5 billion years ago, and it was ejected as a result of the formation of the Karratha crater 5-10 milliom years ago.
“Finding the region where the ‘Black Beauty’ meteorite originates is critical because it contains the oldest Martian fragments ever found, aged at 4.48 billion years old, and it shows similarities between Mars’ very old crust, aged about 4.53 billion years old, and today’s Earth continents,” Dr. Lagain said.
“The region we identify as being the source of this unique Martian meteorite sample constitutes a true window into the earliest environment of the planets, including the Earth, which our planet lost because of plate tectonics and erosion.”
Distribution of the most likely crater sources for Martian meteorites: (a) global context of the 19 crater candidates and location of provinces and rovers (yellow triangles) referred to in the present study; (b, c) magnetic field intensity and remanent magnetization at the surface; (d, e) potassium and thorium concentration at the surface; beige area corresponds to discarded provinces due to the weathered basaltic surface contribution. Image credit: Lagain et al., doi: 10.1038/s41467-022-31444-8.
“This research paved the way to locate the ejection site of other Martian meteorites, in order to create the most exhaustive view of the Red Planet’s geological history,” said Professor Gretchen Benedix, a researcher with the Space Science and Technology Centre at Curtin University and the Department of Earth and Planetary Sciences at the Western Australian Museum.
“We are also adapting the algorithm that was used to pinpoint Black Beauty’s point of ejection from Mars to unlock other secrets from the Moon and Mercury.”
“This will help to unravel their geological history and answer burning questions that will help future investigations of the Solar System such as the Artemis program to send humans on the Moon by the end of the decade or the BepiColombo mission, in orbit around Mercury in 2025.”
A paper on the findings was published in the journal Nature Communications.
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A. Lagain et al. 2022. Early crustal processes revealed by the ejection site of the oldest Martian meteorite. Nat Commun 13, 3782; doi: 10.1038/s41467-022-31444-8
