“If a comet or asteroid’s approach brings it to within 1.3 astronomical units of the Sun, we call it a near-Earth object.”
If the asteroid measures about 500ft (150m) across, astronomers will consider the object “potentially hazardous”.
The news comes after NASA’s tracking systems watched a 0.6-mile-wide (one kilometre) shoot past Earth on February 15.
Thankfully, Asteroid DB is much smaller and is only estimated to measures between 39.4ft to 88.5ft (12m to 27m) across.
At the lower end of the estimate, the space rock is comparable in width to the length of about one-and-a-half London double-decker buses.
source: express.co.uk