A massive asteroid, capable of wiping out an entire country, is on a near-collision route towards Earth.
The 1000-metre wide mammoth asteroid has sparked fears of an unprecedented disaster, as it travels at a speed of more than 36,000km/h.
Small meteorites pass by Earth regularly, but one of this size is an occurrence that only happens once in 5000 years.
The impact would reportedly trigger earthquakes, tsunamis and devastating changes in climate.
If the asteroid, called 2014-YB35, did collide with Earth, it would unleash an explosive force equivalent to more than 15,000 tonnes.
“Smaller scale events like Tunguska are absolutely a real risk, largely they are undiscovered and so we are unprepared,” Bill Napier, professor of astronomy at the University of Buckinghamshire, told the Daily Express.
“With something like YB35, we are looking at a scale of global destruction, something that would pose a risk to the continuation of the planet,” he continued.
If an asteroid this big was to hit Earth, it is possible that plumes and debris thrown into the atmosphere would change the climate and potentially make the planet uninhabitable.
“The real risk is from comets, which even if the Earth passes through the tail, can generate a massive plume of smoke with hugely significant consequences,” Napier said.
NASA has said they expect the YB35 to pass within about four million kilometres on Friday.
The rock was detected by the Catalina Sky Survey last year and has been closely watched this week.
Astronomers have named June 30 as Asteroid Day to highlight the dangers of potentially dangerous asteroids.
“It just takes one asteroid to completely destroy life, not just humanity, but all species,” said initiative co-founder Grigorij Richters told the Daily Express.