Following its delayed launch apparently due to ISRO row, India's indigenously designed and developed all-weather satellite with the unique day and night imaging capability may be launched on 20 April, a "lucky" day for the space agency.

As preparations for the blast-off from India's spaceport of Sriharikota, get under way, ISRO is looking forward to 20 April to keep its date with the launch. 

RISAT-1, a Radar Imaging Satellite which can take images of the earth during day as also at night under even cloudy conditions, is the first of its kind developed by India and is already at the spaceport after being transported from Bangalore.

India had launched RISAT-2, which was acquired from Israel at $110 million, on 20 April, 2009, and Resourcesat-2 mission took place on the same day last year. Both proved to be extremely successful ventures.

According to an ISRO official who spoke to PTI in Bangalore, 20 April was a lucky day for ISRO. The statement should not come as a surprise given the back-to-back failures of GSLV -- one with Russian engine and another with homegrown one.

The 1850 kg RISAT-1, is slated for launch by ISRO's workhorse Polar Satellite Launch Vehicle (PSLV-C19 (XL)) into a 536 km orbit.

The spacecraft's launch, the country's first microwave remote sensing satellite, was delayed by at least a couple of months following the ISRO row, the fallout of the punitive action against four former space scientists for their role in the Antrix-Devas deal, that delayed the preparations. (See: CAG smells a bigger scam in S-band spectrum allocation: report)

RISAT-2 with all weather capability and ability to penetrate through clouds was realised in association with Israel Aerospace Industries. It is primarily a spy satellite, and is being used exclusively for Defence applications, to keep a sharp eye on the borders and the country's neighbourhood.

According to an ISRO official quoted by PTI the RISAT-2 satellite could focus sharply on metallic objects.

He added, the RISAT-1 would be useful for monitoring of agriculture and water resources management, among other applications, adding  that the satellite would not be used for defence applications as RISAT-2 was already doing the job.