The Indian space agency on Thursday said it would launch another of its sharp-eyed surveillance satellite RISAT-2BRI with synthetic aperture radar on Dec 11 evening.

The Indian Space Research Organisation (ISRO) has opened registration for people to view the launch from its gallery at the Sriharikota rocket port.

ISRO said the registration for witnessing the launch of ARISAT-2BRI using its rocket Polar Satellite Launch Vehicle (PSLV) opens on Dec 6 at 8 a.m.

The PSLV rocket is expected to blast off at 3.25 p.m. with RISAT-2BR1.

Piggybacking on the 615 kg RISAT-2BR1 would be four foreign satellites that India will be carrying for a fee.

According to an official, another radar imaging satellite 2BR2 with synthetic aperture radar will soon follow after December 11 mission.

A clutch of such sharp-eyed satellites are necessary to look down at the earth on a continuous basis.

In May this year, ISRO had launched 615 kg RISAT-2B.

The next radar imaging satellite - RISAT-2BR2 - expected to be launched soon will also have two small foreign satellites as piggyback.