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he scale of the battering the Moon received early in its history has been revealed in remarkable new data from two Nasa satellites.
Ebb and Flow - together known as the Grail mission - have mapped the subtle variations in gravity across the surface of the lunar body.
They show the Moon's crust to be a mass of pulverised rock - the remains of countless impacts.
Scientists say the beating was far more extensive than previously thought.
And this observation, they add, has relevance for the study of the Earth's ancient past.
It too would have been pummelled in the first billion years of its existence by the left-over debris from the construction of the planets.
It is just not obvious today because the Earth's surface has been constantly remodelled through time as a result of plate tectonics. All its early scars have long since healed.
"If you look at how highly cratered the Moon is - the Earth used to look like that; parts of Mars still do look like that," explained Prof Maria Zuber, Grail's principal investigator from the Massachusetts Institute of Technology, US.
"This period of time when all these impacts where occurring - this was the time when the first microbes were developing.
"We had some idea from the chemistry [of ancient rocks] that Earth was a violent place early on, but now we now know it was an extremely difficult place energetically as well, and it shows just how tenacious life had to be to hang on," she told BBC News.
Prof Zuber was speaking in San Francisco at the American Geophysical Union (AGU) Fall Meeting, the world's largest annual gathering for Earth and planetary scientists.
Her 300kg Grail twins have spent much of the past year mapping the Moon's gravitational field from an operational altitude of 55km.
Michael Bisping Dan Bobish Vagam Bodjukyan Kotetsu Boku Tony Bonello
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