The Polar Satellite Launch Vehicle (PSLV) in its thirtieth flight (PSLV-C28), will launch three identical DMC3 optical earth observation satellites ‎on July 10 at 21.58 hrs.

The rocket will also carry two auxiliary satellites from UK --- CBNT-1, a technology demonstrator earth observation micro satellite built by SSTL, and De-OrbitSail, a technology demonstrator nano satellite built by Surrey Space Centre.

With the overall lift-off mass of the five satellites amounting to about 1,440 kg, this mission becomes the heaviest commercial mission ever undertaken by Antrix, the commercial arm of Indian Space Research Organisation.

The 62-and-half hour countdown commenced this morning at 07:28 hours, the ISRO said.

The Mission Readiness Review Committee and Launch Authorisation Board on Tuesday night cleared the starting of the 62 and half hour countdown.

The three DMC3 satellites, each weighing 447 kg, will be launched into a 647 km Sun-Synchronous Orbit (SSO) using the high-end version of PSLV (PSLV-XL) from Satish Dhawan Space Centre, Sriharikota (SDSC-SHAR), the spaceport of India.

PSLV-C28 will be the ninth flight of PSLV in ‘XL’ configuration.