MOSCOW, July 15 (RIA Novosti) - The launch of the Discovery space shuttle will probably be postponed until July 18, Viktor Romishevsky, deputy head of the Federal Space Agency, said.

"I think this was the right decision, as the "launch window" lasts until July 30," Romishevsky said.

Vladimir Popovkin, the Commander of the Space Forces, said that testers adhered to the principle that any doubts should be cleared up on the ground.

The launch of the Discovery space vehicle was aborted on July 13, after an external fuel tank sensor failed.

If Discovery is not launched by the end of July, the next launch window will be in September. The window depends on the position of the international space station in orbit and NASA's determination that the launch is held in daylight so that it can visually monitor the shuttle's shield.

In 2003, during a Columbia launch a piece of foam insulation debris hit the space vehicle's wing and compromised its shield. This incident initially went unnoticed. The shuttle burnt up in the atmosphere on its way back to the Earth, killing all seven crewmembers.

Since then, Russian piloted Soyuz space vehicles and Progress cargo vehicles have been delivering crews and cargoes to the international space station.