A massive space rock that once made its way onto a space agency’s warning list for potentially dangerous objects is scheduled to pass by the Earth this Thursday, September 18, 2025.
The space object, officially designated Asteroid 2025 FA22, is expected to make its near approach at 3:41 AM Eastern Time in the U.S., bringing it a little more than twice as far from Earth as the Moon. At no time during its pass will the object represent a threat, according to the European Space Agency (ESA).
In a statement this week, the agency said the object is estimated to be between 130 and 290 meters across, making it comparable in size to 70 Pine Street, a 67-story New York skyscraper also known as the American International Building.
An Asteroid That Raised Alarms
Discovered in March, Asteroid 2025 FA22 was initially spotted with the Pan-STARRS 2 telescope. At that time, calculations on its orbital path indicated there may be a possibility that it could eventually impact Earth by around 2089.
Based on this small impact probability, the ESA temporarily elevated 2025 FA22 to the top of the Risk List maintained by the ESA. “However, high-priority follow-up observations soon allowed astronomers to refine the asteroid’s trajectory and rule out any impact risk,” the agency said this week.
The object was deemed to no longer be a threat in May and has since been removed from the ESA’s Risk List of potentially dangerous asteroids.
Astronomers Are Eager to Glimpse 2025 FA22
Although it is no longer considered a potential threat, that doesn’t mean astronomers aren’t interested in observing 2025 FA22 during its close pass by Earth tomorrow morning.
Among the groups that will be monitoring its movement is the International Asteroid Warning Network (IAWN), which is managing an observation campaign to measure various characteristics of the asteroid, as well as to collect and share information about it.
“The goal of the IAWN 2025 FA22 campaign is for the global planetary defence community to test its ability to measure the orbit and physical characteristics of a large asteroid passing relatively close to Earth, and to coordinate collaboration and information sharing amongst its members,” the ESA said this week.
What Are Astronomers Looking For?
As 2025 FA22 passes Earth, astronomers will train their telescopes on the object to observe qualities that include its motion, brightness, and position during its journey.
Features like the asteroid’s albedo—the way light is reflected off of it—will also be examined, which could reveal clues about what kinds of materials it is carrying with it.
To help achieve this, the ESA says that astronomers will employ a remote sensing capability known as asteroid polarimetry, which studies the polarization of sunlight scattered by the surface of space rocks passing relatively close to Earth.
Through such observations, scientists hope to be able to collect additional information about how asteroids behave when passing close to Earth, which may one day offer vital knowledge if any space objects are deemed to be a potential threat due to a possible collision.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.