Two hefty asteroids passed close to Earth last Wednesday. At least five are more set to swing near by January's end, but none are dinosaur-killers, scientists who track them said. One of Wednesday's close-approaching asteroids measured between .6 and 1.8 miles in diameter, a big enough space rock to cause catastrophe if it collided with Earth. But asteroid 7341 1991 VK got no closer than 7 million miles, nearly 24 times the distance from the Earth to the Moon.