Science News: A massive near-Earth asteroid is set to make its closest pass by our planet in roughly four centuries. Numbered 152637 and known as 1997 NC1, the obje. A massive near-Earth asteroid is set to make its closest pass by our planet in roughly four centuries. Numbered 152637 and known as 1997 NC1, the object will fly past Earth on June 27 at a distance of about 2.57 million kilometres, equal to nearly 6.... [4546 chars]