Starlink is a satellite internet constellation operated by American aerospace company SpaceX, providing coverage to over 60 countries. It also aims for global mobile phone service after 2023. SpaceX started launching Starlink satellites in 2019. As of August 2023, Starlink consists of over 5,000 mass-produced small satellites in low Earth orbit (LEO), which communicate with designated ground transceivers. In total, nearly 12,000 satellites are planned to be deployed, with a possible later extension to 42,000. SpaceX announced reaching more than 1 million subscribers in December 2022 and 1.5 million subscribers in May 2023. Starlink has had a key role in the Russo-Ukrainian War.The SpaceX satellite development facility in Redmond, Washington, houses the Starlink research, development, manufacturing, and orbit control teams. The cost of the decade-long project to design, build, and deploy the constellation was estimated by SpaceX in May 2018 to be at least US$10 billion (equivalent to US$10.73 billion in 2021). In January 2017 SpaceX expected more than $30 billion in revenue by 2025 from its satellite constellation, while revenues from its launch business were expected to reach $5 billion in the same year.Astronomers have raised concerns about the effect the constellation can have on ground-based astronomy and how the satellites will add to an already congested orbital environment. SpaceX has attempted to mitigate astronometric interference concerns with measures to reduce their brightness during operation. The satellites are equipped with Hall-effect thrusters allowing them to orbit raise, station-keep, and de-orbit at the end of their life. Additionally, the satellites are designed to autonomously and smoothly avoid collisions based on uplinked tracking data.