NASA is currently monitoring a group of asteroids that are headed for Earth. One of the approaching asteroids is large enough to wipe out a major city if it hits the planet.

According to NASA’s Center for Near Earth Object Studies (CNEOS), the first asteroid that will enter Earth’s neighborhood this week is called 2019 UT. It is currently traveling at an impressive speed of 25,120 miles per hour and has an estimated diameter of almost 50 feet.

This asteroid is expected to fly past Earth on Oct. 22 at 3:28 am EDT from a distance of only 0.00606 astronomical units or roughly 563,000 miles away.

Closely following 2019 UT is an asteroid that has been identified as 2019 UZ. It is currently approaching Earth with a speed of 22,000 miles per hour. CNEOS estimated that it is about 52 feet long.

2019 UZ will approach Earth in Oct. 23 at 4:29 pm EDT. During this time, the asteroid will be about 0.01462 astronomical units or roughly 1.4 million miles from the planet’s center.

The third asteroid that will visit Earth is called 2019 UD. According to CNEOS, this one is currently moving with a velocity of almost 7,000 miles per hour and is about 79 feet wide. The agency noted it will fly past Earth on Oct. 24 at 9:05 am EDT from a distance of 0.02207 astronomical units or about 2 million miles away.

On Oct. 25, a total of four asteroids will approach Earth. Although most of these asteroids are about 118 to 190 feet wide, the biggest one has a diameter of 3,248 feet. Known as 162082 (1998 HL1), this asteroid’s currently traveling at a speed of 25,076 miles per hour.

Given its current size and velocity, this massive asteroid is capable of causing a high level of destruction if it hits Earth. Due to its size, an impact event caused by the asteroid can wipe out an entire city.

Fortunately, this asteroid will approach Earth from a very safe distance of 0.04155 astronomical units or about 3.9 million miles away during its upcoming visit. The other three asteroids, namely 2019 TQ2, 2019 UQ and 2019 TG5 will fly past Earth from varying distances ranging from 0.01101 astronomical units or 1 million miles away to 0.03679 astronomical units or about 3.4 million miles away.