One more successful flight. 10th Jan 2007, ISRO begins the year with a spectacular launch of its proven and reliable work horse, PSLV C7. And this time to launch four payloads together, two Indian and two foreign. A feat in itself!Whenever ISRO launches a satellite, I remember two events. I will tell you both of them before we look in the present launch in more detail. Year 2005, there was a lecture by Prof. Mashelkar, the mastermind of CSIR and a world renowned chemist. He was talking about the scientific achievements of India. He gave a very interesting example. At various places on earth there are satellite receiving stations which receives data from many different satellite form many different countries viewable from that station and then send them to the respective owners. He was visiting one such earth station in South Africa in 1997. He asked them to show the best and the highest resolution images they receive there. So the officials took him to one corner to show him some examples. He was pleasantly surprised to see that the images were from IRS 1C. Yes, IRS stands for Indian Remote Sensing satellite. In fact till early 1999 IRS imagery was the highest resolution imagery available commercially in the world!

The second event was in May 1998, when India tested 5 nuclear devices. And the American intelligence agency CIA was breaking its head for failing to detect them in spite of employing two of their most sophisticated and high resolution spy satellite (The Key Hole series, KH 11 particularly) to look for these attempts by India. One Indian official made statement ‘It was not their failure but it was our success.’. Because the Indians knew exactly when the satellite was in a position to see them and what would be more visible and what will be difficult to see. And they took all the care to hide what they where doing. What he meant was clearly stated by one of the CIA official as ‘You can’t fool a country by these imaging satellites which has half a dozen imaging satellites of their own and has an experience of having more than a dozen satellites on space. They know when we are watching them and when we are not.’ Well if this does not prove ISRO’s ability then have look at the turnover of Antrix Corporation, a branch of ISRO which sells the imagery form these satellites allover the world including all the developed countries. They earned nearly 400 Crore Rupees last year form these images beamed back by our remote sensing satellites.

Lets try and understand what ISRO as achieved in it’s last about 40 years of existence. A typical launch consists of two parts, a launch vehicle and a payload. The technologies involved in both are completely different with their own complexities and challenges. And yes both these businesses are expansive (though ISRO manages with less than 50 times the annual budget of NASA!). ISRO followed a two pronged strategy, learn to build the payloads like communication and remote sensing satellite and launch them with the foreign help and with foreign launchers. And meantime learn to make launching rockets starting from very small ones like SLV-3 which could launch only 40 kg payload in the lower earth orbit (nearly400 km), to ASLV, PSLV (about 2000 kg in 1000km orbit) and GSLV (about 2000 kg to 36000 km geostationary orbit). Each step, more and more complex and the technology import becoming more and more impossible. Most of the technology ISRO had to develop on their own. Yes, contrary to the belief of some pessimist Indians and the ignorant media (most of whom incidentally can’t even distinguish between making a Diwali rocket and making a satellite launch vehicle), the whole vehicle including all the intricate technologies was made in India. It is disheartening to see that some people made stupid statements that these are all copied from Russia. This is the prize our scientists get for their work and dedication. More so when for the same job in Europe or USA they will get more than 10 times the money and all the luxurious life. Anyway, this can be discussed in details later. There is no point dishonoring the achievement of our scientists and engineers by giving attention to such stupid comments. The famous Cryogenic engine development is a very good example of how developed countries like USA tried to stop India from buying the technology from Russia and finally ISRO developed it on its own at the cost of delaying the GSLV project by few years.

Today ISRO stands on the strong foundations, where it has fulfilled the dream of people like Vikram Sarabhai, Satish Dhawan , A. P. J. Abdul Kalam and many others. Now they are looking to the future with projects like Chandrayaan-I and II, GSLV Mk-II, Mk-III and Mk-IV and may be manned space mission. On the payload front, ISRO has been doing a world class work. The INSAT series of geostationary communication satellites and IRS series, TES, Oceansat, Resourcesat, Cartosat-1 and now cartosat-2 forming the earth imaging system. Out of these, TES, Catrosat -1 and II can take pictures with resolution better than 1 meter. Yes, equal to or better than the highest resolution we see on the famous Google Earth.

First, about the launch vehicle, PSLV C7. It was the tenth PSLV launch and except the first one all nine in a row are successful. The details of the design are available on the net in all the details. The best place is obviously the web site of ISRO. This time it’s job was to carry four payloads, namely Cartosat-2, Space Recovery Experiment capsule, a small 56 kg Indonesian satellite and a 6 kg Argentinean satellite. All four tobe injected in about 640 km orbit Polar Sun Synchronous orbit . And PSLV did that job perfectly. The injection in the orbit was so perfect that the main satellite Cartosat-2 had to consume much less fuel to do the final correction to its orbit than expected and hence the operational life of the satellite will be about 2 years more than planned. For all non technical people, it is sufficient to say that, this launch involved a very complex operation and only a few countries can do this. All the four objects have to separate without colliding with each other out in the space. No scope for mistake.

About the payload. The main payload was cartosat-2. It is remote sensing satellite with a one panchromatic camera which can take images at a resolution better than 1 meter. This imagery will be used by Indian and foreign customers for various applications like urban planning, surveying cities, crop estimation, etc. Also this imagery is regularly used by the Indian armed forces. (For example, in Kargil war the IRS images were used by the Indian army as well as air force to track and attack the insurgents. That experience led to to the launch of Technology Experiment Satellite (TES) in Oct. 2001 which is exclusively used by the Indian Armed forces.).

The second and a very unique payload was SRE. It is the first time for ISRO that a space probe is launched, it will stay in the orbit for about 12 days, performing some experiments and then it will be made to reenter the atmosphere. It will land in the Bay of Bengal with the help of parachutes and will be recovered with the help of the coast guards. This is the fore runner for the manned space missions. Though the reentry and recovery is not as spectacular as the launch, it is in some sense more complicated. The capsule’s exterior surface will be heated to temperatures close to 2000 oC due to the friction with the air, and obviously we are not interested in frying our future astronauts in side, the inside temperature should not cross 40 oC or so. (Well, the DRDO team has achieved this already for the Agni missile though!). This is the experiment people are looking forward to. The success or failure of this experiment is going to decide the future course for ISRO.

Related links: Web-site of ISRO, Official announcement of PSLV launch, News on CNN IBN about the launch (video)