In late December 2024, astronomers first detected asteroid 2024 YR4, which quickly garnered attention due to initial calculations indicating it was on a potentially dangerous trajectory that could pose a threat to Earth in 2032. Dubbed an "asteroid city killer," the object raised alarms as it could cause widespread destruction if it were to collide with our planet.
However, further observations have drastically reduced the risk of an Earth impact. According to recent findings, the probability of a collision has plummeted from a peak of 3.1% in February 2025 to nearly zero, now standing at just 0.00078%. While the threat to Earth has diminished, there remains a small chance—approximately 3.8%—that 2024 YR4 could collide with the Moon. If this lunar collision occurs, it would not significantly impact Earth but would present a unique opportunity for scientific research, as reported by 24 Channel referencing NOIRLab.
To better understand this asteroid, astronomers from Eureka Scientific and other institutions conducted detailed observations using telescopes. They analyzed light curves and gathered data in the infrared range, which clarified both the origin and physical characteristics of 2024 YR4. Surprisingly, the asteroid has an unexpectedly flattened shape, resembling a hockey puck rather than the typical potato-like form of many asteroids. Its estimated diameter ranges from 30 to 67 meters, a size that could potentially cause significant damage if it were to enter Earth's atmosphere.
The shape of 2024 YR4 is indicative of unusual formation processes, which are critical for assessing its structural integrity and behavior during a possible atmospheric entry or deflection attempts. Analysis of its reflective properties suggests that 2024 YR4 likely belongs to the S-type category of asteroids, characterized as dense, stony bodies rich in silicates. This classification distinguishes it from more loosely structured carbonaceous asteroids, which may respond differently to external influences.
Another fascinating aspect of 2024 YR4 is its rapid rotation, completing one full turn approximately every 20 minutes in a retrograde direction. This swift rotation is also significant for collision models and potential deflection strategies. The asteroid originates from the central part of the main asteroid belt, situated between the orbits of Mars and Jupiter. It is believed that the gravitational influence of Jupiter, which typically protects the inner Solar System, may have nudged 2024 YR4 into an orbit closer to Earth.
Researchers emphasize that understanding the shape, composition, and trajectory of such objects is critical for planetary defense. The data collected on 2024 YR4 will not only aid in developing potential strategies for deflecting the asteroid from its course but also enhance observational methods for detecting celestial bodies that may appear unexpectedly in the future.
Interestingly, the potential collision with the Moon could serve as a valuable experiment. If it occurs, scientists would have the opportunity to directly assess the relationship between the size of the asteroid and the crater it creates, providing crucial insights into impact processes within the Solar System.
In recent updates, NASA's calculations indicated a 2.3% chance that 2024 YR4 could collide with Earth, a figure corroborated by the European Space Agency (ESA), which estimated the probability at 2.27%. This increase in risk, compared to earlier assessments, has prompted heightened monitoring by planetary defense offices at both NASA and ESA. The James Webb Space Telescope, with its $10 billion price tag, will be actively tracking this small asteroid.
2024 YR4's dimensions have been confirmed to range from 40 to 90 meters, which could result in significant destruction if it enters the atmosphere. The expected collision date is January 22, 2032, with a potential impact area covering the eastern Pacific Ocean, North and South America, the Atlantic Ocean, Africa, the Arabian Sea, and South Asia.
It's worth noting that these impact assessments are based on dividing the diameter of the Earth by the width of the undefined zone created through modeling the asteroid's trajectory. However, as 2024 YR4 gradually moves away from Earth on an elliptical path, detecting it using conventional means is becoming increasingly difficult. In the coming weeks, even professional four-meter telescopes may struggle to capture it.
Monitoring the trajectory of an asteroid is a dynamic process, with the likelihood of impact fluctuating as new data emerges. Fortunately, humanity has previously demonstrated its ability to deflect asteroids. In 2022, NASA's DART mission successfully showcased the potential to alter the trajectory of a space object using kinetic impact, proving that we possess the technology and knowledge necessary to attempt to protect our planet.
As scientists continue to study 2024 YR4, the focus remains on understanding the implications of its trajectory and composition. The ongoing research not only sheds light on this specific asteroid but also enhances our preparedness for future encounters with potentially hazardous objects.
