Skyscraper-sized asteroid 2025 FA22 to pass Earth Thursday at roughly twice the Moon's distance
European Space Agency says the object poses no immediate threat; flyby will be used to refine orbital and physical data for planetary defense
An asteroid roughly the size of a large city skyscraper will make a close but safe pass of Earth early Thursday, coming within about 520,000 miles (roughly twice the distance between Earth and the Moon) at approximately 3:40 a.m. ET, space agencies said.
The object, designated 2025 FA22, was discovered in March by the Pan-STARRS 2 telescope in Hawaii. Initial uncertainty in its orbit prompted concern that it might pose a future impact risk when it returns to the inner solar system; more recent observations have allowed scientists to narrow its trajectory and remove it from the European Space Agency’s list of potential impactors for the coming decades.
Measurements place the asteroid’s diameter between about 427 and 951 feet (130 to 290 meters), comparable in height to New York’s Chrysler Building. An impact by a body of that size, scientists note, would have the potential to cause severe regional damage, generating blast effects, fires and seismic waves, and — if it struck the ocean — tsunamis and significant atmospheric dust. Those consequences depend on impact location, angle and composition, and no such impact is predicted for Thursday.
The asteroid is traveling at roughly 24,000 miles per hour (about 38,600 kilometers per hour). At closest approach, it will be too dim to see with the unaided eye; amateur astronomers with an eight-inch (20-centimeter) or larger telescope, or powerful stargazing binoculars, should be able to spot it as a faint, moving point of light against the background stars.
Observatories and outreach groups have scheduled observations and broadcasts. The Virtual Telescope Project planned a free livestream beginning Wednesday night at 11 p.m. ET and continuing through the asteroid’s flyby, enabling astronomers and the public to follow the passage in real time.
Space agencies are also treating the encounter as an observational exercise for planetary defense. The European Space Agency said its 2025 FA22 campaign will gather precise positional data, brightness measurements and observations of how sunlight reflects off the object’s surface. Those photometric studies help determine the asteroid’s composition — whether it is rocky or metallic — its surface roughness and reflectivity, and refine models of how its orbit evolves over time.
When 2025 FA22 was first detected, some orbital solutions allowed for a non-negligible chance of future collisions, including a projection that raised concern for a close approach on Sept. 23, 2089. After additional tracking and analysis, ESA removed the asteroid from its list of potential impactors. Current projections indicate future close approaches in 2089 and in 2173, the latter forecast to bring the object within about 200,000 miles (roughly 320,000 kilometers) of Earth, but those distances are subject to refinement as more data are collected.
The close passage on Thursday provides an opportunity to tighten orbital uncertainties and improve long-term predictions. Scientists said that precise measurements of position and velocity during such encounters feed into impact-probability calculations and test observation, tracking and response procedures that would be needed if a genuinely hazardous object were found on a collision course.
Officials reiterated that 2025 FA22 presents no imminent danger. The flyby offers both scientists and the public a chance to observe a near-Earth object and to advance observational techniques and modeling that underpin planetary defense efforts.