A ‘potentially hazardous’ asteroid which is three times the size of a football pitch and travelling at 27,000 miles an hour will pass close to Earth on Monday night.
Although the speeding chunk of rock – named 2000 EM26 – will be 1.6 million miles away it still represents a close shave for our planet in astronomical terms.
It will be tracked by the online Slooh Space Camera which monitors asteroids but scientists say it poses no threat to Earth.
Scientists estimate that 2000 EM26 is around 885 feet (270 meters) in diameter.
During its closest approach, the asteroid will fly about 8.8 lunar distances from Earth.
A potentially hazardous object is a near-Earth asteroid or comet with an orbit that makes close approaches to the Earth and is of a size large enough to cause significant regional damage.
2000 EM26's flyby is almost exactly a year after a meteor unexpectedly exploded above Chelyabinsk, Russia, causing damage and injuring more than 1,000 people with falling glass.
"On a practical level, a previously-unknown, undiscovered asteroid seems to hit our planet and cause damage or injury once a century or so, as we witnessed on June 20, 1908 and February 15, 2013,” said Slooh astronomer Bob Berman.
“Every few centuries, an even more massive asteroid strikes us — fortunately usually impacting in an ocean or wasteland such an Antarctica.
“But the on-going threat, and the fact that biosphere-altering events remain a real if small annual possibility, suggests that discovering and tracking all NEOs, as well as setting up contingency plans for deflecting them on short notice should the need arise, would be a wise use of resources.”
Slooh routinely tracks dangerous asteroids which have the potential to cause significant damage if they hit the Earth.
Their work has the side aim of increasing awareness about the dangers of asteroids, and recruiting members of the public to help by scanning the skies with Slooh robotic telescopes.
Paul Cox, technical research director said: "We continue to discover these potentially hazardous asteroids — sometimes only days before they make their close approaches to Earth.
“Slooh's asteroid research campaign is gathering momentum with Slooh members using the Slooh robotic telescopes to monitor this huge population of potentially hazardous space rocks. We need to find them before they find us.