India has a new chairman at the helm(A position of leadership) at its space agency and a new prime minister, who has put science on top of his agenda. Both are likely to catapult(launch) ISRO into its next growth orbit, writes Hari Pulakkat
Kiran Kumar, the new chairman of the Indian Space Research Organisation (ISRO), has spent all his working life at the Space Applications Centre (SAC) in Ahmedabad. For decades this laboratory performed away from public view, quietly developing instruments and technologies for India's satellites. Kumar kept a similarly low-profile, although he was involved in several key missions. Now both Kumar and his lab are moving to the centre-stage, and not just by virtue of becoming him the chairman.Within ISRO, A S Kiran Kumar has been known to be a quiet but tenacious(Good at remembering) engineer, with a deep technical understanding of satellites and their applications.Over the last few decades, Kumar had been closely involved in developing several satellite applications. He had worked on the development of payloads of satellite missions right from Bhaskara in 1979 to the Mars Orbiter Mission last year. He had closely monitored the journey of the orbiter from the earth to mars, taking crucial technical decisions till the last minute. Now, as the chairman of ISRO, he has a pre-eminent task: expand the applications of space technology along with the technology itself.
In the last few months, PM Modi has been pushing for increased applications of science and technology in the country, and space technology in particular. As the applications increase, the unstated goal is to expand the space programme itself, from building satellites to launch vehicles and specific missions beyond the earth. At some point, it would also mean expanding the domestic manufacturing base, mainly in the private industry, and the commercial ambitions of ISRO through its business arm Antrix. Says Kumar: “As many as 18 teams are working in ISRO with the ministries to find new applications for space technology .“
These teams, along with the ministries, will soon come up with a plan to increase the utilisation of space technology in all ministries. Meanwhile, ISRO has its own full calendar with new projects, some of them expanding the potential use of space technology significantly . It also involves new heavy launch vehicles, new cryogenic and semi-cryogenic engines, a moon and a solar mission and, if there is enough government support, human space missions as well. Also going on under the radar are programmes like air-breathing and reusable launch vehicles. It is a formidable(Extremely impressive in strength or excellence) turnaround for an organisation that was, just two years ago, still not had a fully-successful geostationary launch vehicle.
In March, ISRO will have the first flight of this year: a Polar Satellite Launch Vehicle (PSLV) will put in orbit IRNSS 1-D, the fourth navigation satellite that is part of a constellation of seven satellites supposed to provide indigenous capability in this strategic area. Later this year, it will put the country's first astronomy satellite (Astrosat) in orbit, providing a broad spectrum of instruments for the astronomy community . In between, PSLV will also have a commercial launch, and the Geosynchronous Launch Vehicle (GSLV) Mark II go up one more time, putting GSAT-6 into orbit. After that, all eyes will be on GSLV Mark III and the indigenous cryogenic engine.
The GSLV Mark III has already had a sub-orbital flight last year. On December 18, it lifted off with a dummy cryogenic upper stage and a crew module as a payload. The crew module was ejected at an altitude of 126 km, after which it descended through the atmosphere and landed in the Indian Ocean safely . The next flight of GSLV Mark III, currently scheduled for December 2016, is to go the full distance and put a 4-tonne satellite into geostationary orbit. The first two stages of the vehicle are ready, but the upper stage has to wait for the cryogenic stage that is now being developed at the Liquid Propulsions Systems Centre (LPSC) near Thiruvananthapuram.
There is a marked difference between the two versions of GSLVs. Its Mark II version could put only a 2.5-tonne satellite into geostationary orbit while Mark III can lift 4-tonne satellites. The rockets differ in their design too. Mark II has three stages: a solid first with four liquid strap-ons, a liquid second stage, and a cryogenic third. Mark III has two stages, supplemented with two powerful solid mo tors. GSLV Mark I, now retired, flew with Russian cryogenic engines. GSLV Mark II had indigenous cryogenic engines, but they were re-engineered from the Russian design. GSLV Mark III has larger and completely indigenous(native) cryogenic engines in the upper stage. “It is a completely new vehicle,“ says S Somanath, project director of GSLV Mark III.
The Russian cryogenic engines were small and hence not very powerful: in technical parlance(idiom), they had a thrust of 8-9 tonnes. This was all right for a small vehicle, but not for a heavy lifter like GSLV Mark III. To put a 4-tonne satellite into orbit, the cryogenic engine has to be nearly twice as powerful. The new engine being developed will have a thrust of nearly 20 tonnes, which will be enough to put a large satellite into orbit when combined with powerful lower stages.The new engine will bring with it some advantages and disadvantages as well.
The Russian engines used what is called the staged combustion cycle; burn a bit of the fuel in a pre-burner, and then bring the hot gas into the main chamber to complete the combustion(burning). This results in a highly efficient engine but complicated plumbing(Measure the depth of something) and control systems. It also makes the engine components difficult to test separately. The engine under development uses a gas generator cycle, where some fuel is burned and then used to operate the pumps. Since the hot gases in the pre-burner are not injected into the main combustion chamber, the efficiency of the engine goes down marginally but the engine becomes simple and light.
The gas-generator engine is also loosely coupled, which means the parts can be developed and tested independently before being assembled and tested again as a whole. “All the subsystem tests of the engine are done,“ says K Sivan, LPSC director. “Two levels of integration are also over, and real engine tests are going on now.“ ISRO needs to test three engines over two years and prepare the upper stage to go in the flight. GSLV Mark III development involved the creation of substantial facilities with an investment of at least Rs 1000 crore. Along the way, ISRO has also designed a vehicle that can do more than just put satellites into orbit.“It is a future human-rated vehicle,“ says Somanath. Actual use in a human flight will require additional tests.
To begin with, the vehicle has fewer stages than its predecessor, thereby making it simpler. The control algorithms of GSLV Mark III are different, and it has new electrical controls as well that work in tandem(One behind the other). The rocket has the ability to detect failures and isolate them as well, an important requirement for human-rated vehicles. The actuator a motor has multiple power sources, and only two are required for them to work. Sensors have triple redundancy(Repetition of messages to reduce the probability of errors in transmission). The vehicle commands have some redundancy too. Each vehicle unit has a destruction system. And so on.
Meanwhile, ISRO has started forming concepts to develop a rocket that can put a 10-tonne satellite into orbit. This vehicle would require powerful engines.One candidate is the semi-cryogenic engine, using kerosene and liquid oxygen, whose design is now over. The hardware is being built and facilities being created.When ready, it will be an efficient lower stage with a thrust of 200 tonnes and controllable in flight, good enough to go into the lower stages of a large rocket. ISRO's plans are to use it in the heavy lifter and the reusable launch vehicle.
While future engines and launch vehicles get ready, its old workhorse PSLV will launch a series of novel satellites in orbit. The next PSLV flight in March will put the fourth satellite of the Indian Regional Navigation Satellite System (IRNSS) into orbit. Three more such satellites are to follow IRNSS 1D, thus completing a network with considerable strategic value to the country . PSLV will have a commercial launch too this year, with foreign satellites, and another one to put the Astrosat into orbit roughly over the equator. This satellite will orbit at an altitude of 650 km for five years, thereby augmenting domestic space engineering capability for scientific research.
Astrosat, has been in the works for over a decade. The Tata Institute of Fundamental Research (TIFR) developed three of its five payloads, some of which were quite complicated to build. One instrument, the soft x-ray telescope, took 11 years to build. TIFR has now completed building all the instruments and handed them over to ISRO, which has begun the integration at Bangalore. It will be the world's only multiwave astronomy satellite, another one from NASA having ended its life some time ago. Astrosat has multiple imaging methods: ultraviolet, soft x-ray and hard xrays. “It is a general purpose satellite that can be used for many different studies,“ says K P Singh, professor at TIFR, who was closely involved in its development. Astronomers like Singh will use it for a variety of research. It will look at black holes in the galaxy and beyond. It can look at clusters of galaxies not discovered so far. It can look at stars and exclude those that cannot have planets with life. Astronomers can propose an experiment that will be examined by a team; data from the experiment will be open after about 18 months.
All the five payloads of the Astrosat are now in the clean room and are being assembled. The full satellite will be ready in one month, and tested for another three months. It will be ready for launch by July , and could go up by August. “Everybody in ISRO and the astronomy community is looking forward to the Astrosat,“ says S K Shivkumar, director of ISRO Satellite Centre in Bangalore. It will involve expansion of space applications for ISRO.
So will be the next lunar mission, for which ISRO is developing a rover, a lander and an orbiter. Unlike the previous mission, Chandrayaan-2 cannot be launched by the PSLV . This is because it has a payload supposed to be 2.25 tonne, well outside the capabilities of PSLV-XL. Chandrayaan-1 had a weight of 1.3 tonne. GSLV is supposed to have a few more flights before Chandrayaan-2, and would probably be looked at as a reliable vehicle.
Chandrayaan-2 was planned as a joint project between India and Russia, with Russia developing the moon lander, but the Russians withdrew citing technical reasons. ISRO then decided to develop the rover on its own. The spacecraft is being designed and a six-wheeled rover has been designed already . “It has shaped well,“ says Shivkumar. ISRO has had a review recently . The launch is expected to happen sometime in July 2018.
After that, apart from building routine satellites, ISRO has another major mission in mind: Aditya 1, or a satellite to look at the sun. This is to be located in between the earth and the sun, at a point called Lagrangian Point, where it is supposed to remain for all of its life. There are technical issues, not least of which is the stability of the satellite at the Lagrangian Point. Understanding how the satellite will behave there is a tough problem. Considering the current ambitions of ISRO, even tougher problems would follow in future.
Star Power
ISRO has its hands full with new projects, some of which pushing up the potential use of space technology significantly. These include new heavy launch vehicles, cryogenic and semi-cryogenic engines, a moon and a solar mission and, if there is enough government support, human space missions as well. Plus, you have air-breathing and reusable launch vehicles. And the turnaround seems to be complete
In the last few months, PM Modi has been pushing for increased applications of science and technology in the country, and space technology in particular. As the applications increase, the unstated goal is to expand the space programme itself, from building satellites to launch vehicles and specific missions beyond the earth. At some point, it would also mean expanding the domestic manufacturing base, mainly in the private industry, and the commercial ambitions of ISRO through its business arm Antrix. Says Kumar: “As many as 18 teams are working in ISRO with the ministries to find new applications for space technology .“
These teams, along with the ministries, will soon come up with a plan to increase the utilisation of space technology in all ministries. Meanwhile, ISRO has its own full calendar with new projects, some of them expanding the potential use of space technology significantly . It also involves new heavy launch vehicles, new cryogenic and semi-cryogenic engines, a moon and a solar mission and, if there is enough government support, human space missions as well. Also going on under the radar are programmes like air-breathing and reusable launch vehicles. It is a formidable(Extremely impressive in strength or excellence) turnaround for an organisation that was, just two years ago, still not had a fully-successful geostationary launch vehicle.
In March, ISRO will have the first flight of this year: a Polar Satellite Launch Vehicle (PSLV) will put in orbit IRNSS 1-D, the fourth navigation satellite that is part of a constellation of seven satellites supposed to provide indigenous capability in this strategic area. Later this year, it will put the country's first astronomy satellite (Astrosat) in orbit, providing a broad spectrum of instruments for the astronomy community . In between, PSLV will also have a commercial launch, and the Geosynchronous Launch Vehicle (GSLV) Mark II go up one more time, putting GSAT-6 into orbit. After that, all eyes will be on GSLV Mark III and the indigenous cryogenic engine.
The GSLV Mark III has already had a sub-orbital flight last year. On December 18, it lifted off with a dummy cryogenic upper stage and a crew module as a payload. The crew module was ejected at an altitude of 126 km, after which it descended through the atmosphere and landed in the Indian Ocean safely . The next flight of GSLV Mark III, currently scheduled for December 2016, is to go the full distance and put a 4-tonne satellite into geostationary orbit. The first two stages of the vehicle are ready, but the upper stage has to wait for the cryogenic stage that is now being developed at the Liquid Propulsions Systems Centre (LPSC) near Thiruvananthapuram.
There is a marked difference between the two versions of GSLVs. Its Mark II version could put only a 2.5-tonne satellite into geostationary orbit while Mark III can lift 4-tonne satellites. The rockets differ in their design too. Mark II has three stages: a solid first with four liquid strap-ons, a liquid second stage, and a cryogenic third. Mark III has two stages, supplemented with two powerful solid mo tors. GSLV Mark I, now retired, flew with Russian cryogenic engines. GSLV Mark II had indigenous cryogenic engines, but they were re-engineered from the Russian design. GSLV Mark III has larger and completely indigenous(native) cryogenic engines in the upper stage. “It is a completely new vehicle,“ says S Somanath, project director of GSLV Mark III.
The Russian cryogenic engines were small and hence not very powerful: in technical parlance(idiom), they had a thrust of 8-9 tonnes. This was all right for a small vehicle, but not for a heavy lifter like GSLV Mark III. To put a 4-tonne satellite into orbit, the cryogenic engine has to be nearly twice as powerful. The new engine being developed will have a thrust of nearly 20 tonnes, which will be enough to put a large satellite into orbit when combined with powerful lower stages.The new engine will bring with it some advantages and disadvantages as well.
The Russian engines used what is called the staged combustion cycle; burn a bit of the fuel in a pre-burner, and then bring the hot gas into the main chamber to complete the combustion(burning). This results in a highly efficient engine but complicated plumbing(Measure the depth of something) and control systems. It also makes the engine components difficult to test separately. The engine under development uses a gas generator cycle, where some fuel is burned and then used to operate the pumps. Since the hot gases in the pre-burner are not injected into the main combustion chamber, the efficiency of the engine goes down marginally but the engine becomes simple and light.
The gas-generator engine is also loosely coupled, which means the parts can be developed and tested independently before being assembled and tested again as a whole. “All the subsystem tests of the engine are done,“ says K Sivan, LPSC director. “Two levels of integration are also over, and real engine tests are going on now.“ ISRO needs to test three engines over two years and prepare the upper stage to go in the flight. GSLV Mark III development involved the creation of substantial facilities with an investment of at least Rs 1000 crore. Along the way, ISRO has also designed a vehicle that can do more than just put satellites into orbit.“It is a future human-rated vehicle,“ says Somanath. Actual use in a human flight will require additional tests.
To begin with, the vehicle has fewer stages than its predecessor, thereby making it simpler. The control algorithms of GSLV Mark III are different, and it has new electrical controls as well that work in tandem(One behind the other). The rocket has the ability to detect failures and isolate them as well, an important requirement for human-rated vehicles. The actuator a motor has multiple power sources, and only two are required for them to work. Sensors have triple redundancy(Repetition of messages to reduce the probability of errors in transmission). The vehicle commands have some redundancy too. Each vehicle unit has a destruction system. And so on.
Meanwhile, ISRO has started forming concepts to develop a rocket that can put a 10-tonne satellite into orbit. This vehicle would require powerful engines.One candidate is the semi-cryogenic engine, using kerosene and liquid oxygen, whose design is now over. The hardware is being built and facilities being created.When ready, it will be an efficient lower stage with a thrust of 200 tonnes and controllable in flight, good enough to go into the lower stages of a large rocket. ISRO's plans are to use it in the heavy lifter and the reusable launch vehicle.
While future engines and launch vehicles get ready, its old workhorse PSLV will launch a series of novel satellites in orbit. The next PSLV flight in March will put the fourth satellite of the Indian Regional Navigation Satellite System (IRNSS) into orbit. Three more such satellites are to follow IRNSS 1D, thus completing a network with considerable strategic value to the country . PSLV will have a commercial launch too this year, with foreign satellites, and another one to put the Astrosat into orbit roughly over the equator. This satellite will orbit at an altitude of 650 km for five years, thereby augmenting domestic space engineering capability for scientific research.
Astrosat, has been in the works for over a decade. The Tata Institute of Fundamental Research (TIFR) developed three of its five payloads, some of which were quite complicated to build. One instrument, the soft x-ray telescope, took 11 years to build. TIFR has now completed building all the instruments and handed them over to ISRO, which has begun the integration at Bangalore. It will be the world's only multiwave astronomy satellite, another one from NASA having ended its life some time ago. Astrosat has multiple imaging methods: ultraviolet, soft x-ray and hard xrays. “It is a general purpose satellite that can be used for many different studies,“ says K P Singh, professor at TIFR, who was closely involved in its development. Astronomers like Singh will use it for a variety of research. It will look at black holes in the galaxy and beyond. It can look at clusters of galaxies not discovered so far. It can look at stars and exclude those that cannot have planets with life. Astronomers can propose an experiment that will be examined by a team; data from the experiment will be open after about 18 months.
All the five payloads of the Astrosat are now in the clean room and are being assembled. The full satellite will be ready in one month, and tested for another three months. It will be ready for launch by July , and could go up by August. “Everybody in ISRO and the astronomy community is looking forward to the Astrosat,“ says S K Shivkumar, director of ISRO Satellite Centre in Bangalore. It will involve expansion of space applications for ISRO.
So will be the next lunar mission, for which ISRO is developing a rover, a lander and an orbiter. Unlike the previous mission, Chandrayaan-2 cannot be launched by the PSLV . This is because it has a payload supposed to be 2.25 tonne, well outside the capabilities of PSLV-XL. Chandrayaan-1 had a weight of 1.3 tonne. GSLV is supposed to have a few more flights before Chandrayaan-2, and would probably be looked at as a reliable vehicle.
Chandrayaan-2 was planned as a joint project between India and Russia, with Russia developing the moon lander, but the Russians withdrew citing technical reasons. ISRO then decided to develop the rover on its own. The spacecraft is being designed and a six-wheeled rover has been designed already . “It has shaped well,“ says Shivkumar. ISRO has had a review recently . The launch is expected to happen sometime in July 2018.
After that, apart from building routine satellites, ISRO has another major mission in mind: Aditya 1, or a satellite to look at the sun. This is to be located in between the earth and the sun, at a point called Lagrangian Point, where it is supposed to remain for all of its life. There are technical issues, not least of which is the stability of the satellite at the Lagrangian Point. Understanding how the satellite will behave there is a tough problem. Considering the current ambitions of ISRO, even tougher problems would follow in future.
Star Power
ISRO has its hands full with new projects, some of which pushing up the potential use of space technology significantly. These include new heavy launch vehicles, cryogenic and semi-cryogenic engines, a moon and a solar mission and, if there is enough government support, human space missions as well. Plus, you have air-breathing and reusable launch vehicles. And the turnaround seems to be complete
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