A NASA scientist has revealed the list of cities that could be in danger if an asteroid dubbed the "city killer" collides with Earth in 2032.
Astronomers discovered the asteroid, named YR4 2024, was hurtling towards Earth in December and have been keeping a close eye on it ever since.
They have been gathering data to work out its precise orbit and calculate the likelihood of it hitting Earth - and the odds of it colliding with our planet have recently been increased.
The asteroid, which is thought to be between 40 and 90 meters wide, has the potential to unleash energy equivalent to 7.7 megatonnes of TNT should it hit Earth, according to New Scientist, which would be enough to flatten a whole city.
That impact would be around 500 times the power of the atomic bomb dropped on Hiroshima, according to The Independent.
David Rankin, an engineer at the NASA-funded Catalina Sky Survey Project, revealed which areas could be most at risk if the asteroid does collide with our planet.
He revealed to Space.com that the "risk corridor" runs through South America, sub-Saharan Africa, the Indian subcontinent, and Asia.
Rankin explained: "It is likely around the same size as the 1908 Tunguska rock or the Meteor Crater rock. So, while impact effects would be more localized than regional, it certainly has the potential to do serious damage to the area it hits."
Tunguska is currently the largest recorded asteroid to strike the Earth in human histoty, however, there were several bigger impacts in prehistoric times, including the Chicxulub impact, which happened around 66 million years ago and wiped out two-thirds of life on Earth, including the dinosaurs.
While it may sound pretty terrifying, Rankin reassured the public that there's no need to worry just yet.
"People should absolutely not worry about this yet," he told the outlet. "Impact probability is still very low, and the most likely outcome will be a close approaching rock that misses us."
He added: "It is just important to keep in mind that its orbit is still too uncertain to know if it will hit, and right now, the most likely outcome is a miss.
"This impact corridor estimation will eventually go stale with new observations and better orbit calculations."
Currently, that risk corridor goes over many cities including the Colombian capital of Bogotá, Abidjan in Côte d'Ivoire, Lagos in Nigeria, the Sudanese capital of Khartoum, the Indian cities of Mumbai and Kolkata, as well as Dhaka, the capital of Bangladesh.
NASA has been charting the likelihood of it colliding with the Earth in 2032, which was initially at a 1-in-83 chance when it was first spotted.
The odds have been increasing ever since, moving from 1-in-67, to 1-in-53, to 1-in-43, and now to 1-in-38 - a 2.6 percent chance.
The European Space Agency has also been monitoring it and has given a slightly smaller odds of 2.41 percent.
However, with continued monitoring, those odds could very likely change again, as Hugh Lewis at the University of Southampton, UK, explained: "Just because it’s gone up in the last week, doesn’t mean that it’s going to continue to do that."
YR4 2024 is set to fly behind the sun in April, meaning it will be out of view of most telescopes based on Earth, meaning astronomers are limited with how much they can refine their predictions until it comes back into view again in 2028.
Lewis explained: "Any observations we can make between now and when it’s out of view will obviously help us to refine the orbit and to make better predictions.
"That doesn’t necessarily mean that it will go down before April. It could continue to go up, but still ultimately miss us."
Astronomers are also already looking at past data to uncover previously overlooked observations of the asteroid, which may help refine its trajectory.
The James Webb Space Telescope will also hopefully gather crucial information on the asteroid's size and composition in the coming months to establish whether the asteroid could make it through Earth's atmosphere intact and how large of an explosion it could cause if it impacts.
Lewis revealed: "That will help us determine what we need to do about it, because if it’s a stony asteroid, that’s very different from a high proportion of iron-metal asteroid."
He revealed that a stony asteroid would potentially break up during impact but an iron-rich asteroid could cause far worse damage as "the mass makes a huge difference in terms of the energy and whether or not the atmosphere has an effect on it."
Since January, NASA has put YR4 2024 at a level three on the Torino Scale, which charts the danger of NEOs (Near Earth Objects) which measure over 65 feet in diameter and have a 1 percent or greater chance of deep impact.
According to the scale, this "city-killer" asteroid is a "close encounter, meriting attention by astronomers” and has a "1 percent or greater chance of collision capable of localized destruction.”
NASA has previously successfully tested technology designed to deflect asteroids heading for Earth, notably during the Double Asteroid Redirection Test (DART) mission in 2022, which redirected an asteroid twice the size of YR4 2024.
China is also set to undertake a similar asteroid-redirection test on a smaller asteroid in 2027.
Other space agencies are also working on contingency measures for YR4 2024, as well as preparing for any necessary intervention.