'God of chaos' asteroid Apophis could experience major changes during 2029 flyby, study reveals

The massive asteroid Apophis, about 1,100 feet long, is expected to pass extremely close to Earth on April 13, 2029 — closer than many satellites. Named after the Egyptian god of chaos, Apophis was initially thought to pose a significant risk, but recent calculations confirm it will safely pass by Earth, coming within 20,000 miles.

However, this close encounter could trigger tremors and landslides on the asteroid’s surface, according to a new study. Earth’s gravity will likely cause quakes on Apophis, potentially displacing rocks and reshaping its surface. These tremors, though not as strong as earthquakes, could be powerful enough to move boulders around on Apophis.

Additionally, Apophis doesn’t rotate like a typical planet but "tumbles" unpredictably. This tumbling effect could increase or decrease in speed due to Earth’s gravitational pull, which may cause more rock movements and even landslides on its slopes.

NASA’s OSIRIS-APEX mission, a repurposed spacecraft from a previous asteroid mission, is set to observe Apophis up close during this encounter. Over 18 months, OSIRIS-APEX will study the asteroid’s surface changes and chemical makeup, aiming to confirm if Earth’s gravity reshapes Apophis as expected.