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    For Stonehenge’s Altar Stone, an Improbably Long Ancient Journey

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    A six-ton megalith at the heart of the archaeological site traveled more than 450 miles to get there, a new study concludes.Near the center of the roughly 5,000-year-old circular monument known as Stonehenge is a six-ton, rectangular chunk of red sandstone. In Arthurian legend, the so-called Altar Stone was part of the ring of giant rocks that the wizard Merlin magically transported from Mount Killaurus, in Ireland, to Salisbury Plain, a chalk plateau in southern England — a journey chronicled around 1136 by a Welsh cleric, Geoffrey of Monmouth, in his “Historia Regum Britanniae.”Since then, the accepted provenance of the Altar Stone has shifted, spanning a range of possible sites from east Wales and the Marches to northern England. On Wednesday, a study in the journal Nature reroutes the megalith’s odyssey more definitively, proposing a path much longer than scientists had thought possible.The researchers analyzed the chemical composition and the ages of mineral grains in two microscopic fragments of the Altar Stone. This pinpointed the stone’s source to the Orcadian Basin in northeast Scotland, an area that spans Inverness, the Orkney Islands and Shetland. To reach the archaeological site in Wiltshire, the megalith would have traveled at least 465 miles by land or more than 620 miles along the present-day coastline if it came by sea.“This is a genuinely shocking result,” said Rob Ixer, a retired mineralogist and research fellow at University College London who collaborated on the project. “The work prompts two important questions: How and why did the stone travel the length of Britain?”Stonehenge features two kinds of rocks: larger sarsens and smaller bluestones. The sarsens are sandstone slabs found naturally in southern England. They weigh 20 tons on average and were erected in two concentric arrangements. The inner ring is a horseshoe of five trilithons (two uprights capped by a horizontal lintel), of which three complete ones still stand.Richard Bevins examining Bluestone Stone 46, a rhyolite most probably from north Pembrokeshire, on Wales’s southwest coast.Nick Pearce/Aberystwyth University.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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      Mystery of Mona Lisa’s Location May Be Solved

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      A mash-up of geology and art history has identified a likely setting for one of the world’s most famous paintings.She’s been smeared with cake and doused with acid. Vigilantes have stolen her, and protesters have defaced her. She’s been lasered and prodded, displayed for the masses, and relegated to her own basement gallery. More recently, thousands urged billionaire Jeff Bezos to buy her, and then eat her.There is no bottom, it seems, to the mysteries of the Mona Lisa, the Leonardo da Vinci painting that has captivated art lovers, culture vultures and the rest of us for centuries. Who is she? (Most likely Lisa Gherardini, the wife of an Italian nobleman.) Is she smiling? (The short answer — kind of.) Did da Vinci originally intend to paint her differently, with her hair clipped or in a nursing gown?While much about the art world’s most enigmatic subject has been relegated to the realm of the unknowable, now, in a strange crossover of art and geology, there may be one less mystery: where she was sitting when da Vinci painted her.According to Ann Pizzorusso, a geologist and Renaissance-art scholar, da Vinci’s subject is sitting in Lecco, Italy, an idyllic town near the banks of Lake Como. The conclusion, Pizzorusso said, is obvious — she figured it out years ago, but never realized its significance.“I saw the topography near Lecco and realized this was the location,” she said.The nondescript background has some important features; among them, a medieval bridge that most scholars have held as the key to da Vinci’s setting. But Pizzorusso said it is rather the shape of the lake and the gray-white limestone that betrays Lecco as the painting’s spiritual home.“A bridge is fungible,” said Pizzorusso. “You have to combine a bridge with a place that Leonardo was at, and the geology.”We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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      Geologists Make It Official: We’re Not in an ‘Anthropocene’ Epoch

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      The field’s governing body ratified a vote by scientists on the contentious issue, ending a long effort to update the timeline of Earth’s history.The highest governing body in geology has upheld a contested vote by scientists against adding the Anthropocene, or human age, to the official timeline of Earth’s history.The vote, which a committee of around two dozen scholars held in February, brought an end to nearly 15 years of debate about whether to declare that our species had transformed the natural world so thoroughly since the 1950s as to have sent the planet into a new epoch of geologic time.Shortly after voting ended this month, however, the committee’s chair, Jan A. Zalasiewicz, and vice chair, Martin J. Head, called for the results to be annulled. They said the members had voted prematurely, before evaluating all the evidence.Dr. Zalasiewicz and Dr. Head also asserted that many members shouldn’t have been allowed to vote in the first place because they had exceeded their term limits.After considering the matter, the committee’s parent body, the International Union of Geological Sciences, has decided the results will stand, the union’s executive committee said in a statement on Wednesday.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More