That's when SkyTerra-1, one of the largest communications satellites ever built, will be launched into space on a Russian Proton Breeze M rocket from the Baikonur Cosmodrome. If the launch is successful, the satellite will achieve orbit 22,000 miles above Earth and start receiving radio commands after about nine hours.

The craft is one of two that will . The service, which will be sold wholesale to other carriers that can offer it to consumers, will combine satellite voice and data coverage with a fast LTE (Long-Term Evolution) network in select areas. Users will be able to use one device and switch from one network to the other depending on their location.

Satellite-based mobile services have had limited success in the mainstream market, thanks in part to large and expensive devices and fairly expensive rates. LightSquared says it has advantages that will interest more users. For one thing, devices that will carry both its satellite and its LTE services will be about the same size as other smartphones, with no external antenna. Size and cost will be driven down by the introduction of a single chip from Qualcomm, due on the market next year, that's equipped to connect with satellite and a broad range of other mobile networks.

But SkyTerra-1, and a twin that will be launched later as a backup, is also a key asset, according to LightSquared spokesman Tom Surface.

"It's got much more power, much more capacity and capability than satellites that have been launched up to this point," Surface said.