Because of the size of the YU55, about the size of an aircraft carrier, relative to the earth, it should not have any substantial effect on the gravity interaction between the Earth-Moon system. Astronomers also say that there is no cause for concern or any danger of impact on the Earth.
According to NASA, the last time that a space rock the size of asteroid YU55 passed this close to the Earth was in 1976. At that time, astronomers were not aware of the asteroid until it passed by.
As far as astronomers who track the thousands of asteroids and comets in our solar system know, there should not be another asteroid of this size passing so close to the Earth again until 2028.
As of 2:45 PM EST yesterday (Nov. 7th) the asteroid was approximately 860,000 miles (1.38 million kilometers) away from Earth. Radar tracking of 2005 YU 55 has begun today from the Arecibo Planetary Radar Facility in Puerto Rico.
Watch Video of asteroid 2005 YU55 which will pass very close to Earth.