SpaceX begins “significant reconfiguration” of Starlink constellation

SpaceX's Starlink constellation of satellites is an amazing example of taking advantage of what lots of access to Earth orbit can do for humanity. With over 9,000 satellite nodes on orbit, it brings high speed web access to pretty much every place on Earth. The trades for buying the time on the network get better every couple of days when a new batch of satellites goes up. Stephen Clark, writing at Ars Technica starts his observation this way:

The year 2025 ended with more than 14,000 active satellites from all nations zooming around the Earth. One-third of them will soon move to lower altitudes.

What's going on?

About 4,400 of the company’s Starlink Internet satellites will move from an altitude of 341 miles (550 kilometers) to 298 miles (480 kilometers) over the course of 2026, according to Michael Nicolls, SpaceX’s vice president of Starlink engineering.

“Starlink is beginning a significant reconfiguration of its satellite constellation focused on increasing space safety,” Nicolls wrote Thursday in a post on X.

The maneuvers undertaken with the Starlink satellites’ plasma engines will be gradual, but they will eventually bring a large fraction of orbital traffic closer together. The effect, perhaps counterintuitively, will be a reduced risk of collisions between satellites whizzing through near-Earth space at nearly 5 miles per second. Nicolls said the decision will “increase space safety in several ways.”

In the years that the Starlink constellation has been getting put into place, the amount of orbital debris at the lower orbital layers Starlink uses has gone down. It's inevitable that if more satellites are put into lower orbits, the Starlink satellites will be packed more tightly. The counter to that is tighter control of the movements each of the satellites will be achieved. 

There’s another natural reason for reconfiguring the Starlink constellation. The Sun is starting 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 reducing air density in the uppermost layers of the Earth’s atmosphere, a meaningful factor in planning satellite operations in low-Earth orbit.

With the approaching solar minimum, Starlink satellites will encounter less aerodynamic drag at their current altitude. In the rare event of a spacecraft failure, SpaceX relies on atmospheric resistance to drag Starlink satellites out of orbit toward a fiery demise on reentry. Moving the Starlink satellites lower will allow them to naturally reenter the atmosphere and burn up within a few months. At solar minimum, it might take more than four years for drag to pull the satellites out of their current 550-kilometer orbit, according to Nicolls. At the lower altitude, it will take just a few months.

Lowering the orbits will enhance performance of the network, due to things most people won't think of. First, the diameter of the antenna's transmit main signal lobe will appear smaller to anything that it might currently interfere with - specifically the neighbors of the person the satellite is transmitting to. Second, one of the reasons the constellation is at the altitude it's currently spread around is that "higher takes longer" (or "farther away takes longer"). The effective delay from transmitting between surface and satellites is called signal latency and the system architects wanted to limit latency as much as they could, which meant to reduce orbital height as much as they could. 

A point worth bringing up is that the current number of satellites is not as big as the constellation can get. 

SpaceX launched 165 missions with its workhorse Falcon 9 rocket last year, and nearly three-quarters of them carried Starlink satellites into space. The company reported its assembly line in Redmond, Washington, churned out new Starlink satellites at a rate of more than 10 per day. 
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Hundreds of Starlink satellites specially modified to beam connectivity directly to smartphones already fly in orbits as low as 223 miles (360 kilometers).
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Aside from continuing Starlink network expansion with more Falcon 9 launches, SpaceX intends to debut the more powerful Starlink V3 satellite platform this year. Starlink V3 is too big to fit on a Falcon 9, so it must launch on SpaceX’s super-heavy Starship rocket, which has not yet begun operational flights.

Last month a Starlink satellite became disabled on orbit. A commercial imaging satellite owned by Vantor captured this view of the satellite. Credit: Vantor