NASA has confirmed the exact date of the Apophis asteroid flyby: Friday, April 13, 2029. According to the space agency, Apophis will pass within 20,000 miles of Earth's surface, a distance that brings it closer than the ring of geosynchronous satellites orbiting the planet. This will be the closest approach by an asteroid of this size in recorded history, NASA said. The flyby will occur at 5:45 p.m. EDT, with the asteroid traveling at approximately 30,000 miles per hour. NASA's Center for Near Earth Object Studies (CNEOS) has been tracking Apophis since its discovery and refined its orbit using radar and optical observations.
The flyby will be a rare celestial event visible to the naked eye in the night sky, NASA reported. Observers in the Eastern Hemisphere will have the best view, as the asteroid will be visible without a telescope during its closest hours. Major media outlets note that such an event occurs roughly once every few thousand years, making it a once-in-a-lifetime opportunity for skywatchers. The asteroid will appear as a bright, fast-moving star-like object, visible from dark skies in Europe, Africa, and parts of Asia. In the Western Hemisphere, the asteroid will be below the horizon during its closest approach, but some regions may catch a glimpse before dawn. Amateur astronomers are encouraged to use binoculars or small telescopes for a better view. NASA plans to livestream the event and coordinate with observatories worldwide to maximize observations.
This will be the closest approach by something this large currently known. Apophis will be visible to the naked eye for several hours, and Earth tides will probably change its spin state.
Apophis was discovered in 2004, according to multiple reports. The asteroid is approximately 1,230 feet (375 meters) across, though some sources list its width as 1,115 feet (340 meters), reflecting a discrepancy in reported size. Both estimates agree that Apophis is large enough to cause significant damage if it were to impact Earth. The asteroid was discovered by astronomers at the Kitt Peak National Observatory in Arizona. Its name, Apophis, comes from the Egyptian god of chaos, reflecting the initial concern about its potential impact. The asteroid's shape is elongated, and it rotates every 30.5 hours. Radar images from 2021 revealed a peanut-like shape, suggesting it may be a contact binary. Its surface is likely composed of silicate rock and metal, similar to other near-Earth asteroids.
Initial calculations in 2004 suggested Apophis could potentially collide with Earth in 2029, 2036, or 2068, major media outlets report. NASA originally assigned Apophis a 2.7% chance of causing catastrophic damage to Earth, according to the agency. However, all threat from Apophis was eliminated following fresh radar observations in 2021, NASA confirmed. The 2.7% probability was the highest ever recorded for a large asteroid at the time. The potential impact in 2029 was ruled out after additional observations in 2006, but the 2036 and 2068 possibilities remained until 2021. The 2021 radar observations at the Goldstone Deep Space Communications Complex and the Green Bank Telescope provided precise measurements that ruled out any impact for the next century. The asteroid's orbit is now well understood, with uncertainties reduced to a few kilometers.
NASA has stated that Apophis poses no collision threat to Earth for at least 100 years. The agency's OSIRIS-APEX mission and the European Space Agency's Ramses mission are planned to rendezvous with Apophis after the flyby, according to major media reports. These missions aim to study the asteroid's composition and structure, as well as how Earth's gravity may alter its spin state. NASA said the flyby will provide a unique opportunity to observe an asteroid up close and gather data that could inform planetary defense strategies. The agency also noted that Earth's gravitational pull may cause seismic activity on Apophis, potentially revealing its internal structure. Scientists are particularly interested in how the close encounter might change the asteroid's rotation and surface features. The OSIRIS-APEX mission, formerly OSIRIS-REx, will arrive at Apophis shortly after the flyby and conduct a detailed survey for 18 months. ESA's Ramses mission, still in development, aims to launch in 2028 to study Apophis before and during the flyby. These missions represent a coordinated international effort to understand near-Earth objects and improve our ability to predict and mitigate potential impacts. The data collected could also shed light on the formation and evolution of the solar system. NASA emphasized that Apophis poses no danger, but its close approach serves as a natural experiment to test observation and response capabilities. The agency continues to monitor the asteroid's trajectory and has ruled out any impact risk for the foreseeable future. Additionally, NASA's DART mission, which successfully altered an asteroid's orbit in 2022, provides a template for future planetary defense. The Apophis flyby will be used to test rapid-response observation networks and international coordination protocols. Scientists also hope to study tidal forces and potential surface changes caused by Earth's gravity. The combined data from OSIRIS-APEX and Ramses will provide a comprehensive picture of Apophis, from its interior structure to its surface composition. These insights will help refine models of asteroid behavior and improve impact risk assessments for other near-Earth objects.