Chennai, July 4 An Indian rocket is readying for its heaviest mission on July 10 to put into orbit five British satellites alltogether weighing around 1,440 kg from the space port in Sriharikota, the Indian space agency said Saturday.

According to the Indian Space Research Organisation (ISRO) its Polar Satellite Launch Vehicle (PSLV) is scheduled to carry aloft five foreign satellites on July 10.

The four stage/engine PSLV rocket in XL variant is expected to blast off at around 10 p.m. from the Sriharikota space centre in Andhra Pradesh around 80 km from here. The 62.5 hours countdown will start on July 8 at around 7.30 a.m.

Of the five, three are identical DMC3 optical earth observation satellites weighing 447 kg. These will be put into a 647 km sun-synchronous orbit.

Of the other two satellites, CBNT-1 weighs 91 kg and is also an optical earth observation technology demonstration microsatellite, while the De-OrbitSail weighs 7 kg. This is an experimental nano satellite for demonstration of large thin membrane sail and drag deorbiting.

The three DMC3 and the CBNT-1 satellites are built by Surrey Satellite Technology Ltd.

The De-OrbitSail is built by Surrey Space Centre.

According to ISRO, accommodating the three DMC3 satellites each with a height of about three metres within the existing payload fairing or the heat shield of the PSLV was a challenge. Thus, a circular L-adaptor and a triangular Multiple Satellite Adapter-Version 2 (MSA-V2), were newly designed and realised by ISRO for this specific purpose.

France\'s SPOT 7 satellite weighing 714 kg was the heaviest single foreign satellite carried by a PSLV rocket till now. It was launched on June 30, 2014..

India to launch five British satellites on July 10