SpaceX Starlink: What It Is and How Satellite Internet Works

Traditional satellite internet relies on geostationary satellites about 35,786 kilometers above the equator. Signals take a long time to make that round trip, so latency is typically around 600 milliseconds — too slow for video calls or gaming.^[1][2]

Starlink satellites orbit much closer, at roughly 550 kilometers. At that altitude latency drops to a few tens of milliseconds.^{[2][3][12][13]} The trade-off is that each satellite covers a smaller area and moves quickly across the sky, so thousands are needed to keep every region continuously connected — a scale only possible because SpaceX's reusable Falcon 9 rockets made launching them affordable.^[3][4]

A Starlink kit centers on a flat "phased-array" dish. Rather than physically turning to track satellites, it steers its beam electronically, switching seamlessly from one satellite to the next as they pass overhead.^[2]

Data travels from the dish to a satellite and then either down to a ground station connected to the internet or across the constellation using optical inter-satellite links — lasers that pass traffic between satellites at the speed of light in a vacuum.^[2][3] The laser mesh allows service over oceans and polar regions far from any ground station.^[2]

Each satellite has krypton- or argon-fueled ion thrusters to hold its orbit, and at the end of its life it deorbits and burns up in the atmosphere, helping keep low Earth orbit clean.^[2][3][12]

SpaceX announced its satellite-internet plans in 2015, launched two test satellites in 2018 and deployed its first batch of 60 operational satellites in May 2019.^{[3][4][10][11][14]} Public beta service began in 2020, and Starlink expanded rapidly across North America, Europe, Oceania and beyond.^[3]

Growth has been extraordinary. Starlink surpassed 10 million subscribers in mid-2026, and SpaceX's first quarterly report as a public company in August 2026 showed 12 million subscribers, with Starlink revenue up 66% year over year.^[5][6] SpaceX passed 10,700 Starlink satellites launched in 2026 while deploying at a record pace.^[7][15] Starlink provides the majority of SpaceX's revenue, helping fund Starship and Mars.^[6]

Starlink now serves many markets. Starlink Maritime connects cargo ships, cruise ships and yachts; Starlink Aviation brings high-speed Wi-Fi to major airlines; and portable plans serve RVs and campers.^[2][4]

Its direct-to-cell service, developed with mobile carriers such as T-Mobile in the United States, lets ordinary smartphones send texts and use data from satellites where there is no cell tower — a lifeline in remote areas and after natural disasters.^[5] Starlink has also been deployed for disaster relief and emergency response around the world.^[3][4]

SpaceX's next-generation Starlink V3 satellites are far larger and more capable than earlier versions and are designed to launch on Starship. Each is intended to add much more network capacity than its predecessors.^[4][8] On July 24, 2026, Starship Flight 13 deployed the first 20 operational V3 satellites, and Flight 14 was set to carry more on Starship's first orbital mission.^[8][9]