Two medium-sized asteroids on track for Earth flyby but pose no threat, NASA says

The rocks will safely pass about 14 lunar distances from Earth, beyond the moon, or about 3.5 million miles away, NASA officials said.

Near-Earth asteroid 2010 C01 is about 400 to 850 feet in size and will pass Earth on Friday just after 11:30 p.m. EDT.

The second asteroid, 2000 QW7, is larger -- a little less than a half-mile long at an estimated 950 to 2,100 feet in size -- and will fly by Saturday just before 8 p.m. EDT.

"These asteroids have been well observed—once since 2000 and the other since 2010—and their orbits are very well known," Lindley Johnson, planetary defense officer and program executive for NASA's Planetary Defense Coordination Office, said in a news release on the asteroids.

"Small asteroids pass by Earth this close all the time, Johnson said.

NASA described these asteroids as near-Earth objects and said the orbits of NEOs, including comets, that circle the sun, can bring them into Earth's neighborhood - within 30 million miles of Earth's orbit.

The space agency said the asteroids are debris remnants left over from the birth of the solar system 4.6 billion years ago.