25-hour countdown for PSLV launch begins

Tirupati: ISRO on Friday commenced the 25-hour countdown for its dedicated commercial mission to launch two Singapore satellites into orbit.

The launch would be done by using the Polar Satellite Launch Vehicle (PSLV)-C55 at the Satish Dhawan Space Centre-Sriharikota Range (SDSC-SHAR) at Sriharikota in Tirupati district.

The countdown for the launch of PSLV-C55/TeLEOS-2 began at 1.19pm on Friday.

The 44.4m tall rocket, with a lift off mass of 238 tonnes, would lift off at around 2.19pm Saturday from the First Launch Pad at SDSC-SHAR. This is a dedicated commercial mission through NSIL with TeLEOS-2 as the primary satellite and Lumelite-4 as a co-passenger satellite.

During the countdown, propellant filling operations will be carried out in the four-stage vehicle. The two satellites, both belonging to Singapore, weigh about 741kg and 16kg. ISRO’s reliable launch vehicle – PSLV-C55 – will inject the satellites in a 586km Eastward low inclination orbit, about 20 minutes after the lift off.

TeLEOS-2 satellite is developed under a partnership between DSTA (representing the Government of Singapore) and ST Engineering. Once deployed and operational, it would be used to support satellite imagery requirements of various agencies within the government of Singapore.

The satellite carries a synthetic aperture radar (SAR) payload. It would be able to provide all-weather, day and night coverage, and be capable of imaging at 1m full-polarimetric resolution.

The LUMELITE-4 satellite is co-developed by the Institute for Infocomm Research (I2R) of A*STAR and Satellite Technology and Research Centre (STAR) of the National University of Singapore. This is an advanced 12U satellite developed for the technological demonstration of the high-performance Space-borne VHF Data Exchange System (VDES).

Using the VDES communication payload developed by I2R and STAR’s scalable satellite bus platform, it aims to augment Singapore’s e-navigation maritime safety and benefit the global shipping community.

Scientists at ISRO have planned to carry out an in-orbit scientific experiment after the satellites were injected into their intended orbit. The mission has PSLV Orbital Experimental Module (POEM), where the spent PS4 stage of the launch vehicle would be utilized as an orbital platform to carry out scientific experiments through non-separating payloads.

The payloads belong to ISRO/Department of Space, Bellatrix, Dhruva Space and Indian Institute of Astrophysics.