Astronomers say a large asteroid will soon harmlessly zip past Earth. The space rock is called 1997 NC1 and was discovered almost three decades ago by an asteroid-tracking system in Hawaii. It’ll make its closest approach Saturday morning, coming within 1.6 million miles. Skygazers with binoculars and small telescopes may be able to spot it as a small point of light passing harmlessly through the sky. It won’t greet Earth from such a distance again until 2133. Space agencies track the paths of asteroids and other space junk so they can keep Earth safe from any possible collisions.