A giant asteroid, known as 2008 KV2, is expected to fly by at a close distance of about 4.2 million miles (6.7 million kilometers) from Earth on Thursday, marking a rare occasion of rock this huge being so close to our planet.

Scientists discovered the asteroid in 2008 and promptly set about calculating how often it has come close to Earth. According to the NASA researchers who produced estimates of its travels between 1900 and 2199, 2008 KV2 orbits the sun, but it doesn't always come that close to our planet. However, after Thursday's trip, 2008 KV2 is expected to pass by Earth again in 2021 and twice in 2022, according to NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California.

NASA is paying close attention to the rock, considering it as a "potentially hazardous asteroid," according to the Center for Near Earth Object Studies at JPL. Although it will be passing relatively far from Earth - the Moon is about 238,900 miles (384,400 km) away from us, and the asteroid will be more than 17 times that distance – its size of 330 meters diameter and the distance at which it will be passing by makes it potentially dangerous.

“A potentially hazardous object (PHO) is a near-Earth object whose orbit brings it within 4.7 million miles (7.5 million km) of Earth’s orbit, and is greater than 500 feet (140 meters) in size,” NASA’s website reads, adding that the agency is monitoring all known near-Earth objects (NEOs) that venture into the zone between 91 million and 121 million miles (146 million and 195 million km) from the Sun.

Observers on Earth will see a moving point of light. The first to spot it will be those located on the East coast of Australia, from which it will travel west across the Indian Ocean, then across Africa. It will be at its closest point just before 6 p.m. EDT when 2008 KV2 will be over the Atlantic Ocean, moving past the Earth with a speed of more than 25,400 mph (40,800 km/h). After that, we won’t see it again until 2021.