Chennai: The countdown has begun as Indian Space Research Organisation (ISRO) gears up to launch LVM-M3/OneWeb India-2 Mission from the spaceport of Sriharikota on Sunday. The 24-and-a-half hour countdown started at 8.30 am on Saturday, ISRO sources said. ISRO will launch 72 satellites of the UK-base Network Access Associates Limited and place them in low Earth orbits.