When Mexico retired its first telecommunications satellites – Morelos 1 and 2 – they turned to their creators at Hughes Space and Communications Company to create replacements. The first replacement was Solidaridad 1, launched along with Meteosat 6 by Ariane rocket from Kourou, French Guiana on 20 November 1993.

Also known as Satmex 3, Solidaridad 1’s name was chosen to indicate its role of uniting metropolitan and rural Mexico with the world. The satellite covered Mexico, with some bands extending to the United States, Caribbean and South America, providing “voice telephony, data communications, television relay, facsimile transmission, business networks … educational TV broadcasts … [and] nationwide mobile services.”

Twelve thousand rural schools across the country received educational programming transmitted through Solidaridad 1, and some relied entirely on these broadcasts.

The satellite was a 1641 kilogram Hughes HS-601 model winged cube with a 21-meter Solar array wingspan providing 3300 watts of power. Antennas on two sides transmitted in the Ku band and C band and the Earthward side had a 26-element dipole array.

Solidaridad 1 was designed to have an operational lifespan of 14 years, but in 1999 suffered failure of its primary SCP (Satellite Control Processor). The secondary SCP was activated, but it too failed the following year.

On 27 August 2000, Satmex received alarms indicating that the backup SCP had failed. After making 65 attempts to re-establish contact, Hughes technicians recommended deactivation. Electrical energy had been drained as the stricken satellite’s Solar arrays had lost alignment with the Sun. Solidaridad 1 was switched off and declared a total loss. Fortunately, $250 million insurance could be applied to construction of a replacement.

This wasn’t the first failure of a HS-601 satellite – various other satellites had undergone failure of one or both SCPs through the growth of crystalline whiskers on tin-plated relays. Engineers switched from tin to nickel plating to solve the problem.

The loss of Solidaridad 1 wiped out a variety of communications services for over 100 clients, who needed to be relocated in the following days to other satellites in the Satmex fleet, as well as to other operators. Restoring educational television services to the 12,000 rural schools required manual reorientation of antennas toward new satellites, and classes missed during this period were rebroadcast.

Solidaridad 1 is still up there today – stuck in geostationary orbit as it could not be moved to a graveyard. The Ariane rocket body that launched it is also visible.

Boeing Solidaridad Fact Sheet