MOSCOW, Jan. 13 (Xinhua) -- The Russian modules on the International Space Station will realize uninterrupted communications with the ground by 2013, a space industry insider said Wednesday.

    Russia plans to launch two tracking and data relay satellites -- "Luch-5A" and "Luch-5B" -- in 2011, said the unnamed expert, adding that a third satellite, "Luch-4," would be launched in 2013.

    After the three satellites enter their designated orbits, astronauts on the ISS Russian modules will be able to communicate with the ground 24 hours a day.

    Russian astronauts currently can only contact the ground at areas covered by information stations located in Russia. Otherwise, they would have to use U.S. satellites.

    After the three satellites become operational, they could also coordinate with low Earth orbit satellites and Russian modules on the ISS to receive telemetry and research data, and transmit the data back to Russian ground stations.