Countdown for India’s Mars Orbiter Mission (MOM) starts on Sunday as ISRO gears up for the country’s first inter-planetary venture, a shining star in the country’s space programme.

The launch of Mars Orbiter spacecraft is scheduled on November 5 at 2:36 pm IST onboard PSLV-C25 from Satish Dhawan Space Centre SHAR, Sriharikota, which means that it’s going to be a 56-hours-plus countdown, which commences at 6 am on Sunday.

Bangalore-headquartered Indian Space Research Organisation also plans to undertake a launch rehearsal on Thursday (October 31). “Almost all the steps to be carried out during the countdown are checked during the rehearsal,” an ISRO official said. “Everything is progressing well”.

“We have only five minutes launch window,” Chairman of ISRO K Radhakrishnan, also Secretary in the Department of Space and Space Commission Chairman, said here.

He said the mission readiness review is slated for November one, following which the launch authorisation board would give its green signal for the odyssey.

“At that time we will look at the entire performance and the rehearsal and then authorise the countdown,” Radhakrishnan said.

MOM is a Rs 450 crore mission — Rs 110 crore for building PSLV-C25 that would launch the Rs 150 crore spacecraft, with the remaining amount spent on augmenting ground segment, including those required for deep space communication.

Once launched, the spacecraft would go around the earth for about 25 days before embarking on November 30 some 300-days voyage to Martian orbit where it’s planned to reach in September 2014. The minimum life of the spacecraft around Mars is six months but it would certainly outlive it, as similar satellites orbited by other countries have sometimes lasted six-seven years, ISRO officials said.

Mars Orbiter Mission is India's first interplanetary mission to planet Mars with  an orbiter craft designed to orbit Mars in an elliptical orbit.