BANGALORE: While the US government shutdown has inconvenienced millions of Americans, it’s also worrying Isro scientists working on India’s ambitious space programme to Mars.

The Rs 450 crore Mars Orbiter Mission (MOM), scheduled for lift-off at 4.15pm on October 28, could be without Nasa’s communication and navigation support. US space agency Nasa has asked 97% of its 18,000-strong workforce to go on unpaid leave. This has left many of its stations worldwide unmanned. The Isro mission is banking on such stations to track the spacecraft.

If the programme misses the October 28-November 19 launch window, India may have to ground the mission for at least two years.

Nasa had agreed to provide reimbursable communication and navigation support to Indian Space Research Organisation for MOM during the launch and post-launch phases when the spacecraft is out of coverage area of its navigation system.

Nasa was to help in accurate determination/ reconfirmation of orbit and position of spacecraft. “Nasa is currently closed due to a lapse in government funding. I am in furlough status; therefore, I am unable to respond to your message at this time,” was the auto-reply from Nasa spokesperson to TOI’s queries on this matter. Last month, he had told TOI about Nasa support to MOM.

An Isro spokesperson said: “It is too early to comment about this.” Nasa support will cost Isro about Rs 70 crore.

Sources in Isro explained that the launch window is crucial as Mars and Earth will not be in positions suitable for such a programme till the end of 2015 or beginning of 2016. Prof UR Rao, chairman of the national committee of experts which cleared the project, declined to comment, saying it’s a “political” matter.

But he said: “The launch window is important. We’re trying to launch the spacecraft in the beginning of the window. If not November 19, we have time till early December. But once that is lost, we’ll have to wait for two years.”

He said traditionally, Isro avoids launching from Sriharikota during October and November. “It is generally avoided as it is cyclone season. But given the fact that such an opportunity will not be available for years if missed, we scheduled the launch and are hoping that weather does not play spoilsport.”

The spacecraft which left Bangalore on Wednesday, reached launch site Sriharikota on Thursday evening. With components of the launch vehicle PSLV C 25 already at the launch site, integration of the spacecraft will begin on October 10.

