Countdown Begins: ISRO to Launch Singaporean Satellites on 16 Dec

With the blast off hours away, have a look about what’s so special about this launch.

PSLV C30 Take off. (Photo: ISRO)

The launch of six Singaporean satellites using an Indian rocket Polar Satellite Launch Vehicle (PSLV) is slated to blast off at 6 pm Wednesday from the first launch pad at Satish Dhawan Space Centre (SDSC) SHAR, Sriharikota.

The Indian Space Research Organisation (ISRO) tweeted about progress at the launch pad.

PSLV-C29 on the First Launch Pad with Vehicle Assembly Building in background. (Photo: ISRO)

A live broadcast of the launch will begin at 5:30 pm. A telecast will be available on Doordarshan and can also be viewed on a webcast on ISRO’s website.

The Satellites

Out of the six satellites, the 400 kg earth observation satellite called TeLEOS-1 is the main passenger for the PSLV rocket, hence the ISRO has named the mission TeLEOS.

TeLEOS-1 is Singapore’s first commercial earth observation satellite designed and developed by ST Electronics.

The other five co-passenger satellites are VELOX-C1 (123 kg), VELOX-II (13 kg), Kent Ridge-1 (78 kg), Galassia (3.4 kg) and Athenoxat-1.

TeLEOS-1 and Nanosats on Payload Adaptor of PS4. (Photo: ISRO)

Geared for Research

Apart from launching the six foreign satellites, ISRO will also be testing the rocket’s fourth stage/engine’s ability to restart after it is cut-off, around 17 minutes into the flight.

Technically speaking, India will be testing a multiple burn fuel stage/rocket engine for the first time.

The restart and shut off of the fourth stage engine is done as a first step towards launching multiple satellites but in different orbits

Senior ISRO official

“Restarting a rocket engine soon after it is shut off is a critical technology that has to be mastered. Once a rocket engine is activated, then the heat generated is very high. The trick is to cool it down in the space and to restart it at a short gap,” an industry expert told IANS.

“By that time the rocket’s engine has to be cooled down. This part of the experiment is very critical,” he explained.

The PSLV’s fourth stage/engine will be restarted just over 67 minutes into the flight or 50 minutes after the engine was cut-off.

At the time of restart the fourth stage will be in a lower altitude of 523.9 km while the satellites were ejected at 550 km altitude.

Hoisting of the third and fourth stages of PSLV-C29 during vehicle. (Photo: ISRO)

So far in 2015, ISRO has launched 14 satellites (three Indian and 11 foreign) from its rocket port in Sriharikota. Thirteen satellites were launched with PSLV rocket and one communication satellite – GSAT-6-with geosynchronous satellite launch vehicle.

The successful launch of the six Singaporean satellites will take ISRO’s total flights of foreign satellites to 57.