Sunday, July 26, 2009

Pakistani satellite Badr-B

Although Pakistan has only operated one small satellite in LEO (Badr-A, 16 July - 20 August 1990, orbited as a secondary payload by a Chinese booster), the country's modest space program has long been oriented toward remote sensing applications. A data processing infrastructure has been established to exploit Earth observation data transmitted by Landsat, NOAA, and SPOT satellites. As a next step, the Space and Upper Atmosphere Research Commission (SUPARCO) is preparing for the commercial launch of a simple Pakistani satellite with Earth imaging capabilities.

Initially, it was expected that the SUPARCO would launch the second Badr-II satellite during 1993. However, the target could not be achieved. The Badr-II will help Pakistan in the creation of infrastructure for space qualified system and acquisition of know-how and capability in the field of satellite attitude control.

This gravity gradient stabilised small Earth Observation satellite was designed by Space Innovations Limited [SIL] of the United Kingdom. While spacecraft sub-systems are SIL designed and manufactured, the spacecraft integration is being performed by SUPARCO of Pakistan, demonstrating the use of relatively inexpensive microsatellite missions in the field of space technology transfer. Most of the equipment used in the satellite was acquired in Pakistan to stimulate the local software industry. BADAR-B would conduct four major on-board experiments viz earth imaging, use of radiation dosimeter, data storage and forwarding and charged battery experiment.

There are four objectives of the project. First Badar-2 has a CCD camera through which the earth's imaging could be done. Second, there are equipment in the satellite with the help of which signals sent to it, that is, e-mail etc, could be stored. These signals might be forwarded later for onward delivery. The satellite would also be able to measure the radiation through a dosimeter. The last objective is to carry out the battery-end-of-charge-detection. The successful launching of the satellite would also demonstrate Pakistan's ability to guide and control satellites from the ground. The successful operation of the CCD camera on board the Badar-2 satellite would be a first step towards the acquisition of know-how for taking pictures of earth from specialized digital cameras.

The cost of making Badar-2 was considerably more than the first satellite's. Badar-2 is far more complex and sophisticated than Badar-1. The satellite is made of an aluminium alloy and had a total mass of 68.5kg. It would be launched in a circular orbit of 1050km with an orbital period of 106 minutes. A typical pass over Pakistan would last between 10 to 15 minutes.

The 50-kg Badr-B now in final development will be a cube with side dimensions of 45 cm and a gravity-gradient stabilization system. The project plan envisions a 2-3 year mission for a CCD camera in an 800-km, sun-synchronous orbit.

A plan to launch Badr-B in 1994 did not materialize, and it was hoped that a ride could 1995 or 1996. About eight years after the launch of its first satellite Pakistan was ready for the launch of the second. The launching was supposed to be done from the Baikonour Cosmodrome, Kazakhstan in late August 1999 on a Zenit-2 rocket [the main satellite to be launched was Russian ]. Four satellites--one each from Pakistan, Malaysia, Morocco and the US are mounted on the bigger Russian satellite. As per convention the satellite would be known as Badar-2 after its launch. The anticipated launch date subsequently slipped to early 2000.

In November 1999 Dr Abdul Majid, Chairman Pakistan Space and Upper Atmosphere Research Commission (SUPARCO), said Pakistan was planning to develop its own indigenous 'earth observation satellite' within a period of two to three years, although he did not offer any further details

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