The Galaxy 13 / Horizon 1 BSS 601HP satellite will be located at 127°W, between the Hawaiian Islands and the U.S. West Coast, providing coverage to North America, Central America, Alaska and Hawaii. The spacecraft will carry a total of 48 active transponders, 24 in Ku-band and 24 in C-band.

PanAmSat exercised a launch option with Sea Launch for the mission. While the satellite is designed for a 15-year lifespan, Sea Launch's direct insertion into equatorial orbit is expected to yield additional years of service.

The spacecraft's Ku-band payload, which will be known as Horizons-1, is being constructed for the Horizons partnership and will be jointly owned by PanAmSat and JSAT. It will be used to offer a variety of digital video, Internet and data services. Using a Hawaii-based relay station, the satellite's Ku-band payload also will be able to deliver content and services between the United States and Asia. The C-band portion of the new spacecraft will be known as Galaxy 13 and will be operated separately as part of PanAmSat's Galaxy cable neighborhood, which serves the domestic U.S. cable industry. Galaxy 13 will be used to replace capacity on Galaxy 9, which is a Boeing 376 model that will move to a new orbital position and continue to provide services.

Horizons-1's 24 Ku-band transponders will each be powered by 108-watt linear traveling wave tube amplifiers (LTWTAs). Galaxy 13's 24 C-band transponders will each be powered by 40-watt LTWTAs. The spacecraft's solar wings will feature dual-junction gallium arsenide solar cells. These cells will deliver 9.900 kW of power at the beginning of the satellite's 15-year design life.