NASA asteroid tracker: A 721FT asteroid is barreling towards Earth at more than 30,000MPH

Because of these frequent close approaches, space agencies like NASA and the European Space Agency (ESA) keep a watchful eye on their orbits.

NASA said: “By understanding more about these space rocks now, we are better prepared to take appropriate measures in the future.”

Since the asteroid’s discovery in October, NASA has made 82 orbital observations to determine UR2’s size, speed and trajectory.

NASA estimates the space rock measures somewhere in the range of 324ft to 721m (99m to 220m) across.

At the upper end of that estimate, the space rock is comparable in height to the Golden Gate Bridge in San Francisco, US.