PARIS — A U.S. Atlas 5 rocket on Oct. 2 successfully placed Mexico’s Morelos-3 mobile communications satellite into geostationary transfer orbit, a launch that will enable Mexico to deploy its MexSat system despite the loss of an identical satellite in May’s failure of a Russian Proton rocket.

Operating from Cape Canaveral Air Force Station, Florida, launch service provider United Launch Alliance notched its 100th mission since its 2006 founding from a merger of rocket operations of its two shareholders, Boeing Co. and Lockheed Martin Corp.

Morelos-3 builder Boeing Space and Intelligence Systems of El Segundo, California, said the satellite was healthy in orbit and sending signals.

The mission’s success was more important than the Mexican government had intended when it selected both the Lockheed Martin Atlas 5 and Russia’s Proton rockets to launch the identical Centenario and Morelos-3 L-band satellites, both built by Boeing.

The third satellite ordered as part of the MexSat system, a smaller spacecraft called Bicentenario designed to beam C- and Ku-band telecommunications to Mexico’s rural areas as part of the Connect Mexico broadband project, was launched in December 2012. It was built by Orbital ATK of Dulles, Virginia, under contract to Boeing as MexSat system prime contractor.

The two larger spacecraft were to provide L-band mobile communications to Mexico’s armed forces and federal police and to secure two geostationary orbital slots for Mexico.

The Proton rocket’s failure in May changed the equation. The Mexican government pocketed an insurance claim totaling around $390 million but now is forced to rely on Morelos-3 alone, with no backup.

Monica Aspe Bernal, undersecretary at Mexico’s Secretariat of Communications and Transportation (SCT), said the government would not be seeking a rebuild of Centenario, but rather would explore other, less costly avenues to replacing the lost capacity.

Aspe told a satellite conference here Sept. 14 that a public-private partnership could be developed that would give the private sector access to satellite capacity in return for private-sector financing of part of the replacement satellite’s construction. The goal, she said, is to avoid the peak in capital spending that would occur with an outright purchase of a satellite and launch service.

But even without these new spacecraft, she said, with Bicentenario and Morelos-3 in orbit, the MexSat service offering will be maintained as planned.

Morelos-3 is expected to enter operations about 10 months after launch at 113 degrees west longitude. SCT officials have said the still-vacant 116 degrees west orbital slot will remain available to Mexico until 2021, after which it is at risk of being put back into the general pool of orbital positions at the International Telecommunication Union and offered to whoever is next in line.

Morelos-3 is a Boeing 702HP design featuring a 22-meter-diameter L-band antenna to enable users – ground, air and maritime – to maintain links with small terminals. It weighed 5,325 kilograms at launch and is designed to provide 14 kilowatts of power to its communications payload at the end of its 15-year service life.

SCT estimates that there will be 145,000 L-band users of MexSat, in addition to some 100,000 users of the Ku-band civilian broadband service.

The Mexican government spent 21 billion pesos ($1.22 billion at Oct. 2 exchange rates) on MexSat, including a $1.03 billion contract with Boeing for the three satellites.

Peter B. de Selding was the Paris bureau chief for SpaceNews.