On September 4, astronomers discovered a never-before-seen asteroid named 2024 RW1 just eight hours before it flew through Earth’s atmosphere.
The “harmless” meteorite quickly burned up as predicted, creating a bright green fireball that could be seen from 400 kilometers away. Astronomers from the Catalina Sky Survey discovered the meter-wide asteroid 2024 RW1 early on the morning of September 4, according to the European Space Agency (ESA). The Catalina Sky Survey is a NASA-funded project at the University of Arizona’s Steward Observatory near Tucson that scans the sky for potentially hazardous near-Earth objects.
The ESA predicted that the asteroid would break up in the atmosphere and people in the area could witness a spectacular fireball. As predicted, the asteroid exploded at 00:46 local time on September 5 over the western Pacific Ocean near the island of Luzon in the Philippines.
2024 RW1 glows green, likely due to its high magnesium content, according to the American Meteorite Society. Scientists warned locals in advance, allowing them to take photos and videos of the rare event. Asteroids as large as 2024 RW1 enter Earth’s atmosphere about once every two weeks, but astronomers rarely see them because of their small size.
This is the ninth time astronomers have spotted an asteroid before it hit Earth. The most recent was on January 21, when NASA scientists observed a similar-sized asteroid called 2024 BX1 about three hours before it entered the atmosphere and exploded over Berlin, Germany. It was the fastest-spinning asteroid ever recorded. In 2022, another refrigerator-sized asteroid called 2022 EB5 was spotted just two hours before it entered the atmosphere at 40,000 mph and broke up over the North Pole.
Small pieces of fireball meteorites often fall to Earth’s surface after being scattered by the explosion. In January, for example, scientists recovered a piece of the Berlin fireball and determined it was a rare type of asteroid called an aubrite, which is as old as our solar system. However, the odds of recovering any remaining fragments from 2024 RW1 are slim, as it almost certainly fell into the ocean, based on the meteorite’s trajectory.