Mega asteroid the size of a 10-story building will fly past Earth TONIGHT NASA has issued a warning about a colossal Christmas Eve asteroid due to make a close encounter with Earth tonight.
NASA classifies Near-Earth objects as asteroids and comets whose orbits come within 120 million miles (195 million kilometers) of the Sun, allowing them to pass through the vicinity of Earth's orbit.
As more observations are made, the accuracy of an object's orbit improves dramatically, and it becomes possible to predict where an object will be years or even decades into the future – and whether it could come close to Earth.
"The orbit of each object is computed by finding the elliptical path through space that best fits all the available observations, which often span many orbits over many years or decades.
The agency said: "Most near-Earth objects are asteroids that range in size from about 10 feet (a few meters) to nearly 25 miles (40 kilometers) across.
