Chance of 'city-killer' asteroid 2024 YR4 smashing into Earth rises yet again to 3.1%, NASA reports

The probability that a major asteroid, big enough to wipe out an entire city, will hit Earth in 2032 has just increased to 1 in 32, or 3.1%, according to NASA.

On Feb. 7, NASA increased the likelihood that asteroid 2024 YR4 will hit Earth in seven years time from 1.2% to 2.3%. The odds of impact then climbed to 2.6%, and are now at 3.1%, according to the latest data on NASA's Center for Near Earth Object Studies website.

Asteroid 2024 YR4 has an estimated diameter of around 177 feet (54 meters), or about as wide as the leaning tower of Pisa is tall. But while it is too small to end human civilization, the asteroid could still wipe out a major city, releasing about 8 megatons of energy upon impact — more than 500 times the energy released by the atomic bomb that destroyed Hiroshima, Japan.

The good news is that there's still a 96.9% chance that the asteroid will miss Earth entirely, and as researchers learn more about its trajectory, the odds of a strike are likely to decrease to 0%, based on its current risk level in the NASA data. There's also a tiny 0.3% chance that YR4 will hit the moon instead of Earth, Live Science previously reported.

Related: Potentially hazardous asteroids: How many dangerous space rocks lurk near Earth — and can we stop them?

Scientists use a measurement called the Torino Scale to categorize the risk posed by nearby asteroids and comets. With a Torino Scale rating of 3 out of 10, YR4 is capable of localized destruction and passes the 1% impact probability threshold (meaning the risk of a potential impact is estimated to be greater than 1%).

Additional observations will give scientists a more precise estimate of the asteroid's orbit, which usually means they'll be more confident it won't hit Earth. Many other objects on NASA's asteroid risk list have ended up with an impact probability of 0% after more data became available.

A team of scientists was recently granted emergency use of the James Webb Space Telescope, the most powerful space telescope, to study YR4 in the coming months and assess its risk, as well as its true size.

YR4 is currently the only known large asteroid with a more than 1% chance of hitting Earth, according to NASA's planetary defense blog. In the unlikely event that YR4 does collide with Earth, it would probably hit somewhere along a "risk corridor" stretching across the eastern Pacific Ocean, northern South America, the Atlantic Ocean, Africa, the Arabian Sea, and South Asia, according to NASA.