The countdown for the launch of India's first navigation satellite IRNSS-1A is progressing smoothly at Sriharikota in Andhra Pradesh. ISRO officials said, it will be launched at 11.41 PM tonight.

Its for the first time that ISRO is launching a rocket around midnight.

The launch time has been fixed taking into account the orbit and inclination at which the satellite will be injected.

Around 20 minutes after the launch, the Polar Satellite Launch Vehicle, PSLV C22 will inject the navigation satellite at an altitude of 501 kilometer.

The 1,425 kg navigational satellite is intended to provide terrestrial, aerial and marine navigation services and help in disaster and fleet management across the region.

The satellite, with a lifespan of around 10 years, is one of seven satellites constituting the IRNSS space segment.