If you missed the asteroid that came within 745,000 miles of Earth on Monday morning at 8:19 a.m. PST (11:19 a.m. EST), NASA's Jet Propulsion Laboratory reports the flyby was the closest a known asteroid of this size will pass by Earth for the next two centuries.

While 745,000 miles does not sound close to the Earth, asteroid 2004 BL86, which is twice the size of a cruise ship, came closer than any known asteroid of its size.

When asteroid 2004 BL86 flew by our planet yesterday, scientists used the Deep Space Network antenna at Goldstone, California, to capture several stunning images that revealed the asteroid has a small moon.

According to NASA's Jet Propulsion Laboratory, the phenomenon is common:

"The 20 individual images used in the movie were generated from data collected at Goldstone on Jan. 26, 2015. They show the primary body is approximately 1,100 feet (325 meters) across and has a small moon approximately 230 feet (70 meters) across. In the near-Earth population, about 16 percent of asteroids that are about 655 feet (200 meters) or larger are a binary (the primary asteroid with a smaller asteroid moon orbiting it) or even triple systems (two moons). The resolution on the radar images is 13 feet (4 meters) per pixel."

Asteroid 2004 BL86 was initially discovered on Jan. 30, 2004 by a telescope at the Lincoln Near-Earth Asteroid Research (LINEAR) survey in White Sands, New Mexico.

Radar is used to study an asteroid's size, rotation state, shape and surface features, and for improving the calculation of asteroid orbits and trajectory. Radar measurements allow NASA to know asteroid distances and velocities so that computation of asteroid orbits now and into the future can be made.

Tracking asteroids and protecting our home planet from them is a high priority for NASA. The U.S. has the most productive detection and survey for discovering near-Earth objects (NEOs). To date, the U.S. has discovered over 98 percent of the known NEOs.

Sky surveys suggest that scientists have detected most of the bigger-scale celestial objects that could lead to catastrophe if they struck the Earth. None appear likely to strike our planet soon.