The current Starlink constellation consists of hundreds of small, low-cost satellites in low Earth orbit, and the company aims to scale this to thousands. The low altitude is necessary to provide low latency. Current geostationary satellites orbit 26,200 miles from the center of the earth and 22,300 miles above the surface, meaning a signal takes roughly 0.240 seconds to make a round trip. Starlink is currently in orbit at 340 miles, cutting the speed of light lag to almost a hundredth of that.

Bohn, manager for the Network Software team, said, “We have a ground cluster of services figuring out who talks to whom in the network. What’s interesting about our satellites is they are very close. Because of this, a satellite may only be overhead for a few minutes. The antenna on a customer’s roof therefore needs to change which satellite it talks with often.”

“Consider how your cell phone communicates with fixed communication towers. Occasionally your phone needs to switch from one tower to another, but the connection is usually stable,” says Bohn. “For Starlink, one of the main challenges is that our “towers” are orbiting Earth, forcing your path to the internet to change very frequently. My team orchestrates this dance by computing desired network topologies, distributing this plan to the assets in the network, and configuring hardware to make it happen.”