It's still unclear why ISRO decided to postpone the launch -- a decision made just an hour before Chandrayann-2 was scheduled to lift off on July 15th. But the organization tweeted that it was "a measure of abundant precaution." In a statement, ISRO Chairman Dr. K Sivan said, "Team ISRO worked out, fixed and corrected the snag within 24 hours. For the next one and a half day, the required tests were conducted to ensure that corrections made were proper and in [the] right direction."

Chandrayaan-2 will spend 23 days in the Earth's orbit before it begins maneuvering towards its lunar landing. It's expected to touch down on the surface of the Moon on September 7th -- one day after it was originally scheduled to arrive. Once there, the Pragyan rover will study the chemistry, seismography and topography. It will also give India's space program an important boost -- the country plans to launch a space station by 2030.