Ahead of Monday’s launch of Indo-French satellite Saral (Satellite with ARgos and ALtika) and six small spacecraft, scientists began a 59-hour countdown at the Sriharikota launch port at 6.56 a.m. on Saturday.

The PSLV-C20 rocket will lift the satellites into the orbit at 5.56 p.m. It will be the second highest number of satellites to be flown on a PSLV. In April 2008, it put in orbit 10 satellites, including the national Cartosat-2A, on the PSLV-C9 rocket.

The Launch Authorisation Board cleared the mission after reviewing a ground ‘rehearsal’ at the Satish Dhawan Space Centre, according to the Indian Space Research Organisation (ISRO).

Saral weighs around 400 kg and will study ocean surface and the environment using the two devices — ARgos and the ALtika — band altimeter to measure heights.

France’s space research agency CNES has provided the two primary devices and ISRO is responsible for building and launching the spacecraft as per an agreement signed in February 2007 between the two governments.

C20 is the 23 mission of the indigenous PSLV and has been configured in a ‘core-alone’ or bare-bones format without solid strap-on motors. ISRO said this would be the ninth core-alone flight of a PSLV.

Of the six small experimental payloads it will fly for a fee, two each are from universities in Canada and Austria and one each from the U.K. and Denmark.

ISRO initially planned this launch for the memorable date of 12-12-12. However, its officials said it was postponed to complete tests both here and in Sriharikota.

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