The oldest solid material on Earth has just been identified, and it predates the Solar System itself by at least a few hundred million years. The teensy tiny microscopic grains of dust were forged in a distant star somewhere between 5 and 7 billion years ago, according to new research. By comparison, our Sun is just 4.6 billion years old. Eventually, these grains were carried to Earth in a meteorite. "This is one of the most exciting studies I've worked on," said cosmochemist Philipp Heck of the Field Museum of Natural History and the University of Chicago. "These are the...
