SpaceX announced today in Congressional testimony that it plans to start launching a constellation of 4,425 satellites in 2019, providing high speed, low latency broadband and communications services around the globe. The constellation will serve a wide range of customers, including residential, commercial, institutional, and governmental users. SpaceX will begin testing the satellites with a prototype launching this year, and a second test satellite launching in early 2018. The main operational launch campaign would begin in 2019, and continue in phases through 2024. The news was relayed in a statement by SpaceX's Vice President of Satellite Government Affairs, Patricia Cooper, before a hearing organized by Sen. John Thune (R-S.D.), chairman of the Senate Committee on Commerce, Science, and Transportation.

Satellite communications network. Credit: Synertone Communication CorporationSatellite communications network. Credit: Synertone Communication Corporation

Orbiting the Earth at significantly lower altitudes than existing satellite networks, the SpaceX constellation will improve upon the high latencies commonly experienced with satellite internet connections. Current satellite broadband networks like HughesNet orbit at 35,400km, compared to SpaceX’s non-geostationary satellite orbit (NGSO) operating altitude of 1,100km to 1,325km. SpaceX’s constellation will operate in the Ka- and Ku-Band spectrum, with claims of low latencies ranging from 25ms to 35ms, compared to current satellite-based broadband latencies of 603ms to 659ms, and terrestrial-based broadband latencies of 14ms to 52ms.

The system will operate as a “mesh network” with optical links between satellites. It will employ advanced technologies on the ground and in space such as dynamic beam forming and phased array antennas. The satellite network will be accompanied by ground infrastructure including ground control facilities, gateway earth stations, and end user earth stations.

The network will represent a massive increase in the number of satellites orbiting Earth. According to the Union of Concerned Scientists, at the end of 2016 there were 1,459 satellites in orbit. The 4,425 satellites comprising SpaceX’s new constellation would bring that number to 5,884, representing an increase of 303 percent. With increased orbital traffic, collisions adding to the space debris problem become more of a concern.

SpaceX has also proposed an additional fleet of 7,500 satellites orbiting at an even lower altitude that would provide further broadband capacity. This fleet would operate in the V-band.

The satellite constellation could help provide fast, reliable internet to underserved populations in the United States and around the world. According to the Federal Communications Commission, 34 million Americans lack access to broadband service of at least 25 Mbps. And 4.2 billion people, 57 percent of the world’s population, lack access to the internet due to an absence of connectivity or inability to afford connection, according to the United Nations Broadband Commission for Sustainable Development.