"City-killer" asteroid changes course; Here's where it may strike now

Of all things, a massive asteroid named 2024 YR4 recently grabbed our attention as the scientists revealed that the asteroid had a small but concerning chance of striking Earth in 2032, precisely on December 22.

However, the probability of 2024 YR4 hitting Earth has changed now.


Read on to know more about the course of the asteroid.

The change in course:

When first discovered, asteroid 2024 YR4 had a very small chance of impacting Earth on Dec. 22, 2032.

NASA's Center for Near-Earth Object Studies had earlier predicted that it had a 3% chance of hitting Earth in 2032. Just a few weeks later, that chance was revised by NASA and dropped to just 0.28%.

More observation and analysis conducted by the James Webb Space Telescope in late March confirmed the asteroid has a near-zero chance of striking Earth.

However, the chances of a collision have still not been nullified.


According to astronomer Andrew Rivkin, science and technology publication New Scientist reported this week that the asteroid, however, still has a chance of directly colliding with the moon. Rivkin, a planetary astronomer at Johns Hopkins Applied Physics Laboratory, was the co-author of a report analyzing the telescope's observations, which found there is a 2% chance the asteroid could strike the moon in 2032.

That's a small increase from the 1.7% chance predicted by NASA in February.

The asteroid will be studied by the Webb telescope again in May 2025 before it disappears into the outer solar system for the next several years. The James Webb Space Telescope is a powerful observatory that studies the universe. It can study faint objects, and its data is used by multiple international space agencies.

What is an asteroid?

An asteroid is a small, rocky or metallic object that orbits the Sun, typically found in the main asteroid belt between Mars and Jupiter, and is smaller than a planet but larger than a meteoroid.

Here's a more detailed explanation:

Size and Composition: Asteroids are rocky or metallic objects, ranging in size from small rubble piles to objects hundreds of miles across.

Location: Most asteroids are located in the main asteroid belt, a region between the orbits of Mars and Jupiter.

Formation: Asteroids are thought to be remnants from the early formation of the solar system, about 4.6 billion years ago.

Classification: Asteroids are classified as "minor planets" or "planetoids".

Difference from other objects:
Comets: While both asteroids and comets orbit the sun, comets are primarily composed of ice and gas, whereas asteroids are mostly rocky or metallic.

Meteoroids: Meteoroids are small pieces of asteroids or comets that enter Earth's atmosphere, and when they burn up, they create a streak of light known as a meteor.

More on 2024 YR4:

Asteroid 2024 YR4 is a real asteroid that was discovered in December 2024, and while the football-field-sized asteroid initially had a small chance of impacting Earth in 2032, NASA's latest calculations show that it poses no significant threat to Earth in 2032 or beyond.

Here's a more detailed explanation:

Discovery and Initial Concerns: Asteroid 2024 YR4 was discovered on December 27, 2024, by the Asteroid Terrestrial-impact Last Alert System (ATLAS) telescope in Chile. On January 29, the International Asteroid Warning Network (IAWN) issued its first-ever alert for a massive asteroid. However, further observations and calculations have since reduced the likelihood of it impacting Earth to less than 0.001 percent, effectively ruling out any danger.

Size: Although initially the 2024 YR4 asteroid was deemed to have a size of a football field, new infrared observations from NASA's James Webb Space Telescope have decreased the uncertainty of the asteroid's size and 2024 YR4 is now estimated to be 174-220 feet (53-67 meters), about the size of a 10-story building.

Refined Trajectory and Reduced Risk: As more observations were collected and added to the asteroid's orbit calculations, NASA's Center for Near-Earth Object Studies (JPL) was able to refine its trajectory models.

Ongoing Monitoring: Scientists continue to monitor the asteroid's trajectory, and the updated results are always available on NASA's public web pages.

What happens if the asteroid 2024 YR4 hits the moon?

According to NASA, asteroid impacts have been shaping the moon's surface for billions of years. They have also caused craters on Earth. Aaccording to the American Museum of Natural History, asteroids made more contact with both the moon and Earth billions of years ago, but those incidents have lessened over the millennia, leading to "the relatively peaceful present."

It's not clear yet what would happen if an asteroid of this size were to strike the moon. However, according to NASA, if the asteroid were to impact the Moon, it would not alter its orbit.

While a collision with the Moon would likely create a new crater and possibly eject debris into space, it wouldn't affect life on Earth or the Moon’s orbit. Scientists will continue tracking asteroid 2024 YR4 closely. As we learn more, the story of this wandering space rock is far from over.