India's Mars-bound spacecraft is scheduled to complete a key manoeuvre to move out of the earth's orbit into a heliocentric orbit towards the Red Planet in the small hours of Sunday, Indian Space Research Organisation (ISRO) officials say, according to dpa. The operation, code-named the Trans-Mars Injection (TMI), would set the Mangalyaan spacecraft off on a 680-million-kilometre, 280-day voyage away from earth, ISRO spokesman DP Karnik said Saturday. "We will fire an engine for 23 minutes to give it enough speed to push it out of the earth-bound orbit into the trans-Mars trajectory," Karnik said. If the attempt failed for any reason, another injection attempt would take place four days later, Karnik added. After the 280 days, which may involve some minor manoeuvres as the spacecraft nears Mars, the engine would be fired again to decelerate the spacecraft and insert it into a Mars orbit on September 14, 2014. Mangalyaan, meaning "Mars craft" in Hindi, is India's first inter-planetary mission, costing about 80 million dollars. If successful, India's space agency would be the fourth - after those of the United States, Europe and the former Soviet Union - to get a spacecraft to the Red Planet. More than half of all past missions to Mars have failed.