Asteroid 2024 YR4 has 1.2-1.3 % chance to impact Eath on 22nd Dec 2032. More observations could bring this to zero.

Likely 40-100 meters in size.

If it would hit, theoretically could take out a major city, but 71 % of Earth being water, would likely explode over water.

https://www.esa.int/Space_Safety/Planetary_Defence/ESA_actively_monitoring_near-Earth_asteroid_2024_YR4