UPDATED at 2:14 p.m. EDT

PARIS — The SES-3 satellite launched in July 2011, billed as just another plain-vanilla telecommunications satellite to replace another, has led a dashing life in orbit featuring a secret payload, two secret customers and a world tour, according to government and industry officials.

Built by Orbital Sciences Corp. of Dulles, Va., SES-3 was described by its owner, SES of Luxembourg, as carrying 24 C- band and 24 Ku-band transponders designed to replace the AMC-1 satellite covering North America at 103 degrees west longitude.

Undisclosed at the time was that SES-3 also carries two Ka-band transponders. Also left unmentioned was that the satellite is equipped with encryption capabilities that qualify it for MAC-1, or Mission Assurance Category-1, status with encrypted tracking, telemetry and control.

The U.S. Department of Defense defines MAC-1 as the highest of three categories for information deemed vital for the operational readiness or mission effectiveness of deployed and contingency forces.

After its launch, SES-3 was moved to 99 degrees west longitude in geostationary orbit, presumably to prepare for the retirement of AMC-1 and to give Luxembourg-based SES an in-orbit spare in the event that one of several of its satellites with solar array defects needed emergency backup.

Officials said the satellite had a second mission during that period: to “bring into use” a service for another operator that had been unable to launch its own satellite into that position and was about to lose its rights to the slot under international frequency regulations.

But in December, SES-3 began a long drift to Asia, where SES had identified an unnamed business opportunity that industry officials said was the U.S. Department of Defense. By January it was at 108 degrees east.

Tip Osterthaler, president of SES Government Solutions of McLean, Va., said at the time that the ability to move the satellite was “a confirmation of our commitment to provide affordable and vital capacity to our government customers.”

Unfortunately for SES, the government customer in question soon decided it did not need SES-3 and the contract evaporated. U.S. Department of Defense satellite-lease contracts are usually short-duration commitments, but most of them are renewed and SES-3 offered coverage of the Middle East and South Asia.

In July or August, SES-3 began the long drift along the geostationary arc back toward North America, to its originally intended slot at 103 degrees west. But at some point along the way, a commercial customer manifested itself, saying it wished to use SES-3’s Ka-band payload for a short period of time.

That contract was concluded and SES-3 performed the requested Ka-band task. Since September, the satellite has been at 103 degrees west.

SES officials disclosed the Ka-band contract in a Nov. 9 conference call with investors, but declined to identify the customer or specify the purpose or duration of the contract.

SES Chief Financial Officer Andrew Browne said the Ka-band contract helped compensate for the loss of the customer over Asia.

“The customer in question requested that we don’t give any information about the contract,” Browne said.

SES Chief Executive Romain Bausch said the contract was with “a large customer,” and that the business arrived without much advance notice, ended within the quarter and will not be repeated.

SES has done regular business with EchoStar Corp. of Englewood, Colo., which has leased SES-owned satellites to buttress its fleet, most of which is used by EchoStar’s sister company, Dish Network.

EchoStar has said it has multiple Ka-band orbital positions that may be employed to duplicate its North American satellite consumer broadband business in Latin America and other regions.

EchoStar’s EchoStar 17 satellite, a large all-Ka-band craft that is enabling the company’s HughesNet Gen 4 high-speed broadband network, was launched in July and entered commercial service in October.

A government official familiar with SES-3’s voyages said that before it moved to Asia, it spent about three months at 99 degrees west. An EchoStar Ka-band reservation at that slot had been scheduled to expire — having spent seven years without being, in regulatory parlance, “brought into use” — in February.

This official said international regulators were notified that the registered Ka-band orbital position, called USASAT-70V, was brought into service in October, the period during which SES-3 was there.

Bausch said the SES-3 story is an example of finding opportunities even in a market like North America, whose demand for conventional C- and Ku-band satellite bandwidth is not growing and is not expected to grow much in the coming years.

“We always describe the North American market as a flat market,” Bausch said during the conference call. “But here we see there are opportunities. The government is interested in contracting additional capacity for the North American market, for different [government] departments. We see opportunities with the U.S. administration.

“And there are satellite outsourcing opportunities, with EchoStar or others. So there are pockets of growth in the U.S. market.”

Peter B. de Selding was the Paris Bureau Chief for SpaceNews.