The success ratio of lunar missions undertaken in the last six decades is 60 per cent, according to US space agency NASA’s ‘Moon Fact Sheet’. Of the 109 lunar missions during the period, 61 were successful and 48 had failed, it stated. In the early hours of Saturday, Indian space agency ISRO’s plan to soft land Chandrayaan-2’s Vikram module on the lunar surface did not go as per script.