Aidan Thornton, a reader from Minneapolis, has visited the site, now Pipestone National Monument, several times. He wrote to ...

At a conservative estimate, it contains three times the amount of water of all the oceans on our surface. A new study may ...

Two different testing methods found that rocks from an area called the Nuvvuagittuq Greenstone Belt in northern Quebec date to 4.16 billion years ago, a time known as the Hadean eon.