The year 2025 ended with more than 14,000 active satellites from all countries zooming around the Earth. A third of them will soon move to lower altitudes.
The maneuvers will be carried out by SpaceX, owner of the largest fleet of satellites in orbit. About 4,400 of the company's Starlink Internet satellites will travel from an altitude of 341 miles (550 kilometers) to 298 miles (480 kilometers) over the course of 2026, according to Michael Nicolls, vice president of Starlink engineering at SpaceX.
“Starlink is embarking on a major reconfiguration of its satellite constellation aimed at increasing safety in space,” Nicolls wrote in a post on X on Thursday.
The maneuvers undertaken with the plasma engines of the Starlink satellites will be gradual, but will eventually bring much of the orbital traffic closer together. The effect, perhaps counterintuitively, will be a reduced risk of collisions between satellites flying through space around Earth at nearly 5 miles per second. Nicolls said the decision “will increase safety in space in several ways.”
Why now?
There are fewer debris objects at the lower altitude, and although the Starlink satellites will be more densely packed, they will follow choreographed paths divided into dozens of orbital lanes. “The number of debris objects and planned satellite constellations is significantly lower below 500 km, reducing the overall probability of a collision,” Nicolls wrote.
The 4,400 satellites moving closer to Earth make up nearly half of SpaceX's Starlink fleet. By the end of 2025, SpaceX had nearly 9,400 working satellites in orbit, including more than 8,000 Starlinks in operational service and hundreds more being tested and activated.
There is another natural reason for reconfiguring the Starlink constellation. The Sun will begin to quiet down after reaching the peak of the 11-year solar cycle in 2024. The decline in solar activity has the knock-on effect of decreasing air density in the upper layers of Earth's atmosphere, a meaningful factor in planning satellite operations in low Earth orbit.
As solar minimum approaches, Starlink satellites will experience less aerodynamic drag at their current altitude. In the rare event that a spacecraft malfunctions, SpaceX relies on atmospheric drag to drag Starlink satellites out of orbit toward a fiery demise upon reentry. By lowering the Starlink satellites, they can naturally reenter the atmosphere and burn up within a few months. According to Nicolls, at a solar minimum it could take more than four years before air resistance takes the satellites out of their current orbit of 550 kilometers. At lower altitudes it will only last a few months.
