What they talk about when they talk about the GSLV?

The GSLV-F10/EOS-03 mission failed on August 12, 2021. The vehicle faced an issue in it’s third cryogenic stage.

What does ISRO mean when they say GSLV? There is a lot of confusion between the GSLV Mk I and the GSLV Mk II. The YouTuber Gareeb Scientist raised this question in a video he posted on August 8, 2021. He provides the reasons for this confusion.

I believed the first version of the story shared in Gareeb Scientist’s video. I believed that the Mk I was a reference to the GSLVs which flew with the Russian cryogenic engine, KVD-1. And, thought that the Mk II referred to the GSLV which flew with the Indian cryogenic engine, CE-7.5.

This version was shared by ISRO in the brochure of the GSLV-D3 which flew on April 15, 2010. ISRO has removed this brochure from it’s website. But, there is an archived version online as well as on the VSSC website [PDF]. Page two of this brochure carries this explanation.

The Wikipedia page for GSLV still references this explanation and describes variants in this manner. I think that this has contributed to this confusion.

ISRO seems to have changed this version of the story in 2015 in an e-book published on its website, Fishing Hamlet to Red Planet. You need an epub reader to read the book. In an essay by R V Perumal titled, Evolution of the Geosynchronous Satellite Launch Vehicle, he mentions that the GSLV Mk I was actually a modified version of the PSLV with a cryogenic upper stage. However, since the Cryogenic Stage did not work out for the PSLV, hence the idea of the GSLV Mk I was dropped. Perumal was the Project Director for the PSLV and GSLV and later the Director, Liquid Propulsion Systems Center (LPSC). I think I would trust this version.

Since there is no Mk I and all the flights of the GSLV are what ISRO called the Mk II project, it seems ISRO just dropped the Mk II and began calling the launch vehicle GSLV in 2017. This change is also seen on the ISRO website on the GSLV page from 2017.

The GSLV Mk III is a totally different project. I think the GSLV tag got attached to it only because it primarily delivers its payload to a geostationary transfer orbit.

Addendum – August 17, 2021

In response to this blog post @zingaroo replied on Twitter stating that ISRO had always called the GSLVs with the Russian cryogenic engines as the Mk-I and the ones with the Indian cryogenic engines as the Mk-II. He provided two examples of the same from the past.

He presents evidence from the magazine, SPACE-India April-June 2003, Page 11. Also from Gopal Raj’s book Reach for the Stars published in 2000.

It seems ISRO is also re-writing history in a way. It seems that the project started somewhere after 2010.

Does ISRO have any plans?

India’s space programme seems to be stuck in a rut.

India has three broad tracks in it’s space programme – satellites and launch vehicles programme for remote sensing, communications and navigation, planetary exploration and human spaceflight. We are trying to outsource the first to a private industry that is not prepared to handle the responsibility yet. The second is moving in slow motion. The third seems to be pushing really hard to achieve the unachievable. In the recently held, Global Space Exploration Conference 2021, Chairman, ISRO had this to say:

This is a statement that the media in India has run several times. Hence, his statement did not get any media coverage in India. ISRO is going through tough times with the spaceport under lockdown because of the large number of COVID-19 cases.

The United Arab Emirates seems to be having more ambitious planetary exploration plans than India at the moment. They are talking about two lunar missions, they have signed up for the Artemis accords and are planning to send the second astronaut to the ISS soon.

UAE has grown rich on an important natural resource, oil. This resource is limited on Earth. This has helped the nation learn important lessons in importance of natural resources for the development of the country. Hence, they want to be part of the space faring nations who get to decide how space resources are used just like OPEC controls crude oil prices on Earth.

India used to announce plans like this before. Before the Chandrayaan 1 launch, we spoke of landing humans on the Moon by 2020. While factors beyond ISRO’s control delayed the realization of these projects by years, it gave everyone a broad idea of where India was headed. Now, there is just silence in this regard.

Chairman, ISRO in his New Year message had said that the various centers had drawn up decadal plans but so far we have not seen any. When there is no action physically due to valid reasons, this is the right time to think of things. For example, China has been putting out studies about how to get humans to Mars. ISRO has been doing these studies but not publishing them.

The civilian space programme is not secretive. The idea is to use this programme to raise the morale of the workforce, inject excitement for science and commerce in the country and project India’s rising capability in the sector. This communication is an important task that is assigned to Chairman, ISRO.

A Difficult Task – Splitting ISRO and NSIL

me: I made an error in understanding this. I leave this here for record. But, I have corrected this on my newsletter.

I write a weekly newsletter on an Indian perspective to space stuff every Thursday. The edition that I sent out last Thursday (March 11) was a space policy edition.

I specifically covered a report tabled in the Rajya Sabha by the Department-related Parliamentary Standing Committee on Science & Technology, Environment, Forests & Climate Change.

Department of Space Organisation Chart. Image: ISRO.

The Standing Committee asked DoS about the role of India’s space agency, Indian Space Research Organisation (ISRO) with the entrance of NewSpace India Ltd. (NSIL). The Department replied stating that missions such as Gaganyaan, Chandrayaan and advanced technology mission would be carried on by ISRO and the rest would go to NSIL. This answer was presented to Parliament in February 2021. The Standing Committee published the report on 8 March 2021.

It is based on this answer that I said in the newsletter that:

This means that ISRO is going through a period of change as it commercializes parts of it’s operations (PSLV, GSLV, SSLV etc.) and focuses on research. This section thus marks a very important turning point in it’s journey. As shared in this PTI story, NSIL also has ambitions of building satellites and payloads. This would mean parts of works done in each center of ISRO will be commercialized and spun-off into NSIL.

Pradeep’s Space Newsletter #20

On 12 March 2021, NSIL held a press conference (NSIL press note). Here, they announced that they are planning to take over ISRO’s fleet of communications and remote sensing satellites.

I must admit I did not see the satellites bit coming. This is no small task. Managing such a fleet of satellites would need the kind of human resources and expertise that is currently only available at ISRO.

Splitting technical and human resources between ISRO and NSIL will be no small task. This is the turning point that I am referring to in the paragraph above.

DoS had put out a request for proposals (RFPs) from the industry to see if any single or a consortium of industries could develop PSLV for NSIL. This process, they claimed during the press conference will take 6 to 8 months.

This leaves the space sector with several players with them not yet knowing what they have to do. There is Indian National Space Promotion and Authorisation Centre (IN-SPACe), Indian Space Research Organisation (ISRO), NewSpace India Ltd. (NSIL), Antrix Corporation, Space Commission and the Department of Space. The Government will have the task of putting them in order to make the sector boom. A difficult task.

Following The PSLV C-50 mission on Twitter

After a long time, I live-tweeted the launch of the PSLV-C50 mission.

From my newsletter, edition #8

CMS-01 was earlier called GSAT-12R. The change of names is for ISRO’s new naming convention. It has named it’s remote sensing satellites as EOS for Earth Observation Satellite and it’s geostationary satellites as CMS for Communications and Meteorology Satellites. ISRO has provided no rationale for the renaming of satellites.

PSLV-C50 mission consisted of a PSLV flown in it’s XL configuration. XL stands for Extended Length. It’s 6 strap-on boosters are extended in length. It carries 4 ground-lit boosters and 2 air-lit boosters. CMS-01 was the only payload on board. The PSLV placed the satellite in the intended orbit in 1200 seconds. The intended orbit was orbit is 284 km X 20650 km at 17.86 deg inclination.

This is ISRO’s second launch from Indian soil in 2020 and third launch including one from Kourou on board the Ariane V launch vehicle.

In the post-launch press conference, ISRO’s Chairman, K Sivan announced that PSLV-C51, ISRO’s next launch would carry Anand satellite of Pixxel Space. This would be India’s first private satellite launch. Pixxel Space is a remote sensing satellite builder and data provider.

Astrobiology in India

I stayed in Lonar between July 2018 and June 2019. I was aware of the geological interest that the meteorite crater there held for the scientific community. I did not know what interest it held for the astrobiology community. I had the first opportunity to learn more when Jyotirvidya Parisanstha (JVP) hosted a lecture by Prof. Yogesh Shouche of the National Center for Cell Science. The lecture was about how Lonar Lake was a model for extraterrestrial life search! I kicked myself little for missing the lecture. Today’s podcast episode gave me a glimpse of what I probably missed.

Episode 16 of the NewSpace India podcast has Narayan Prasad (NP) in conversation with Siddharth Pandey, PhD. Siddharth heads the Center of Excellence in Astrobiology at Amity University, Mumbai. Below are the show notes from that episode.

Siddharth defines Astrobiology as the study of origin, evolution and distribution of life on Earth and the search for it elsewhere. He says Astrobiology formed the basis for some of the older space programs like NASA and Russia’s Roscosmos because it pertains to some of the fundamental questions that have been important to the human species like are we alone in the Universe and the search for life outside our planet. Siddharth wants to begin connecting to a network of people in India who are interested in Astrobiology. He returned to India after stints in America, Europe and Australia.

Siddharth says that astrobiology related experiments in India began in 2005 with teams led by Dr. Jayant Narlikar based out of IUCAA, Pune and TIFR, Hyderabad among others. This group believed in a theory called Panspermia – which says that life was bought to Earth by an asteroid impact at some point in the Earth’s history. This team conducted balloon experiments out of the field in Hyderabad that led to the discovery of bacteria living in extreme environments in the Earth’s atmosphere.

Siddharth says that the Methane search instrument (Methane Sensor for Mars – MSM) on board the Mars Orbiter Mission is an astrobiology experiment. He says ISRO had developed an astrobiology experiment knowingly or unknowingly. Methane is considered one of the bio-signatures that indicates the existence of life. Hence, existence of Methane corresponds to existence of life. He hopes we have more experiments flying to search for life in clouds of Venus and the surface of Mars. He hopes that the chance to carry micro-gravity experiments on board the 4th stage of the PSLV, SSLV and the upcoming human spaceflight mission, Gaganyaan increases the number of astrobiology experiment that can be designed and carried on these missions.

NP asks Siddharth if the lack of a Space Science roadmap is worrying. Siddharth says that he finds the fact that we have no clear Space Science roadmap concerning especially given ISRO’s plans for missions to Mars and Venus in the near future. He says that several meetings on these experiments have been held but the outcomes of these experiments need to be more widely shared. He hopes that in the future, scientists are involved right mission planning and architecture stage of the mission itself to design better payloads.

Siddharth says that there is a need for a National Committee for Astrobiology that brings together various Government departments like DST, DBT etc to develop a roadmap for Astrobiology and to co-ordinate an astrobiology program. He says that ISRO has been good at developing platforms for astrobiology experiments in space.

He then talks about analog environments that are present in India. He speaks about Ladakh, Kutch, Lonar in Maharashtra and Antarctica. He says that the low atmospheric pressure, low oxygen, high ultraviolet ray exposed environment which are well preserved for centuries in Ladakh provides conditions that are analogous to an early Mars.

He says that hypersaline bacteria and jarosite minerals found in Kutch have been studied by PRL, Ahmedabad and papers have been published in scientific journals. He says that being one of the largest continuous salt expanses make it an interesting field of study for it’s similarities to early Mars.

He says that the impact of a meteorite in basaltic rock, a form of rock formed by melting of volcanic rocks means that it takes longer to weather compared to meteorite impact on other types of rocks.. The site at Lonar, Mahrashtra is one that is most accessible among two other similar sites in the world. He says that Lonar also has a lake formed by a drain of a spring that drains into the crater. This is similar to the landing site for the Mars 2020 which may be going into a dried site where a lake such as the one in Lonar probably existed at some point in Mars’ history. Lonar offers similar basin and depositing mechanisms which scientists can compare and study from.

Siddharth says India has two sites in Antarctica – Maitri and Bharati. Of these, Bharti station is located on Larsemann Hills. The hill is of interest because it is ice-free. This is because geothermal heat prevents ice formation. This means scientists have access to rocks and access to study bacteria living in rocks which survive in dry and cold regions of Earth. It also has a permafrost where the ice has not melted as it is under the soil. Here the ice is preserved for centuries and hence of interest to scientists.

NP then asked about how a person interested in astrobiology can pursue it as a career option. Siddharth says that they are in the process of putting together a website with freely available reading material. Siddharth suggests that interested students can pursue Astrobiology at the post-graduate level after pursuing an under-graduate program in Biology, Physics, Chemistry, Engineering etc.

NP then asks Siddharth about possible citizen science efforts that can be undertaken in astrobiology. Siddharth talks about the development of a Space Citizen Network where citizens can get connected to research groups working in the field. He also suggests that citizens could connect with these groups when they go on field trips. There are plans for a field trip to Kutch in October 2020 and to Lonar in November 2020.

There are also plans for projects that can be undertaken at home. One of the plans is to distribute marbles and citizens can report back after studying microbial colonies that grow under the marble. Scientists are interested in understanding how microbial colonies grow and attach themselves to rocks. They also want to learn what environments support growth of these microbial colonies. This can be in addition to similar amateur astronomy projects like identifying asteroids etc.

NP then asks whether there are plans for an independent road-map for Astrobiology of Government efforts for the same. Siddharth says that plans are afoot to formalize a Society of AstroBiology Education and Research (SABER) that could be registered in Maharashtra. He says that the group had already met twice – once in Lucknow and once in Pune. They hope to develop a roadmap for the future growth of the astrobiology community. They might also consider contributing to mission objectives on future missions to Mars and Venus.

NP asks about raising funding for astrobiology experiments. Siddharth says that there is no single source for funding for astrobiology. Mostly, scientists raise funds from different departments and societies based on either where they are coming from or from organizations that are involved in their area of interest.

ISRO provides funding through its RESPOND and SNAP. He says that they have previously raised funding from companies like Tata Motors and National Geographic Traveller magazine. He is currently also thinking of reaching out to philanthropy houses in Mumbai to access funding for the future projects that they are thinking of undertaking.

Siddharth says that Amity is planning to put together a weekend program called Space for Everyone which would generate awareness about space. At the end the people who complete the program can join the Space Citizen Network. He says that astrobiology popularization has been hurt as there is a lack of credible speakers. He hopes that efforts above address these issues. Amity has also launched India’s plant growth space flight experiment called the Amity Space Biology Experiment -1 (ASBE-1).

On the role of the Media, he says that media should do more than simply cover events. They must provide a forum to discuss, analyze and critique events. He says that it must enable two way discussion between the scientist and the citizens. He says that India must look at reasons for which it is pursuing a scientific program.

NP says India has a strong Biotechnology and Pharmacy industry. He asks Siddharth about what is the scope for Indian biotech and pharmaceutical companies in participating in Astrobiology. Siddharth responds that astrobiology experiments would give these companies an opportunity to research how the human body behaves in microgravity and experiment with chemicals and drugs. He says that while there are applications in fundamental research, it would largely serve marketing purposes currently. Companies could showcase how their products are used in space programs and how their designs can be used in extreme conditions such as in space.

NP then asked where Siddharth sees the future of astrobiology in India. Siddharth replies that he hopes that ISRO works on larger support and infrastructural missions with private sector works on supporting low earth commercial missions. For astrobiology in India, he hopes that there is an active scientific society, meeting often to exchange knowledge and builds cross-domain and inter-disciplinary expertise that is needed. He also hopes India undertakes future missions to the moons of Jupiter and Saturn – Europa and Enceladus, that are considered some of the other sites in our solar system which could support life.

End of show notes.

This podcast also gave me a stream of ideas. We could Astrobiology Cafes to discuss recent developments in the field. As missions progress in this direction, I also think there will be discussions surrounding ethics and safety that arise. I do not see how these are tackled by the astrobiology community. This conversation excited me a lot, opened my eyes to what astrobiology really is about and agree with NP’s comment in the end that it was a dense knowledge transfer rich episode of the podcast. This reminded me so much of my days from 2009 when I developed a Lunar Analog Research Station.

Reporting ISRO

The 15th episode of NewSpace India podcast came out this Friday (January 17). It had Narayan Prasad in conversation with Vasudevan Mukunth. VM is the Science Editor for The Wire. If you do follow their Science stories, it is in quite a league of it’s own (better than most Indian coverage and almost at international standards). He also blogs extensively at Root Privileges and tweets at @1amnerd. Full disclosure that he has been my editor of the two pieces that I have contributed to The Wire.

Here are my notes from listening to the podcast episode for my own future reference:

The coverage of ISRO as a journalist depends on the quality of information and access to sources available to a journalist. It requires more information made available in the public domain and access to sources who can explain the information to a journalist. There is no clear demarcation on when the information is publicly available. In many cases, ISRO uses policy to clamp up when asked tough questions.

NP suggests this might be a top level policy level decision. VM suggests that the policy is that scientists are allowed to speak to journalists as long as their comments are not adversarial. Scientists often err on the side of caution and hence do not speak at all. There is no clear information policy. This ambiguity in information policy means that when a failure occurs, information flow just dries up.

NP describes The Wire’s science journalism with respect to ISRO as being that of piecing together information, for placing things in context and critiquing various aspects of the space program. He suggests that the lack of information has forced The Wire to take to this form of “citizen journalism”. VM replies saying that ISRO clamps up information and they seem to fail to acknowledge other sources of information for the stories. As an example, they fail to acknowledge that NASA could find the Vikram lander and put this news out. Similarly, international experts challenged the DRDO claim of the impact of the ASAT test. ISRO scientist don’t put out such news because they don’t know whether they can say it. Information comes out in the form of tweets, in form of access to ISRO Chairman’s office, some of the press notes or updates on the ISRO website etc.

NP then asked VM to share the toolkit that he uses to cover ISRO given this lack of information. VM replies that he uses Google, CelesTrak (where he’s playing with orbital visualisations), he uses crawlers that frequently crawl on the ISRO website where information is put out but not easily available/visible like PDFs etc, Twitter, WhatsApp and the ISRO sub-reddit. VM shares The Wire story that he did on the ISRO sub-redditors and other sources of ISRO news.

VM and NP think that clamping up when failure strikes is a cultural issue that ISRO needs to tackle. VM sympathises with ISRO with regards to the loss of signal issue during the Vikram landing as they may not be comfortable doing this. He feels that they would have done much better to keep quiet rather than to make absurd claims like 95% mission success etc. This is because of the lack of training of journalists they would report anything that ISRO says without questioning.

At another earlier point in the conversation, VM and NP had discussed that lack of good questions came from lack of well-trained journalists who follow space. VM had then argued that there was no point having good journalists when there was not enough people to answer said good questions. Existing journalists have also been made to bureaucratic hoops to cover ISRO events.

ISRO has also lost many opportunities for public science participation. Finding Vikram and Moon Impact Probe were good use cases. Images could easily have been released of the landing site and help taken from the public to find the lander. Also, NP points out that ISRO had a lot of support from the public in many fora, despite a failure and this makes ISRO statements like the 95% success rate unnecessary.

NP then asks on the possibility of using tools like the RTI. VM says RTI provisions are getting diluted and it is getting more difficult to get information through RTI in other areas. However, an RTI request could easily be blocked citing National Security reasons. So, VM wonders if it is worth the investment of time to apply a RTI query. He also says that information regarding a program under taken by ISRO should be put out voluntarily. VM says that commercial use of ISRO images and spacecrafts like the PSLV launch of Mars Orbiter Mission for the movie, Mangalyaan should have been made available easily for commercial use.

NP suggests that given ISRO’s lack of response, one of the ways in which good questions can be put to ISRO may be through the Parliamentary Standing Committee. He suggests it as one of the ways for getting information from ISRO. VM reiterates his stand that information should be forthcoming voluntarily from ISRO.

They both agree that the issue with answering questioning and putting out information is a cultural issue with ISRO.

NP then asks if there must be independent thinking and tracking of the space program, similar to efforts of T S Kelso and Jonathan McDowell. VM thinks that the lack of information availability makes this sort of analysis difficult in the Indian context.

NP then asks VM about what we can look forward to in the future from The Wire Science. VM says they are looking to add more videos and educational material. He believes that having a more informed audience improves the type of journalism that they can do.

They discuss how more senior and retired ISRO journalists could contribute more in the education and discourse if they wrote after their times at ISRO. VM thinks this is also not part of their culture. The books coming out currently are anecdotal or technical. U R Rao’s book is quoted as an exemption and an example to follow. ISRO scientists like Tapan Misra take to Facebook to write about current events at ISRO.

VM ends by saying that he is happy that more diverse newsrooms are now covering space. He gives Firspost as an example for this, whereas earlier the Hindu science pages was the go-to for this sort of information.

VM has posted an addendum to this conversation on his blog and Ohsin also shares his feedback on the ISRO sub-reddit along with his lament about how ISRO image policy leads to loss of images used for coverage of ISRO on Wikipedia. The about community for ISRO’s sub-reddit page perhaps encapsulates the whole episode: For anything related to Indian Space Agency we love but hardly know.

Chandrayaan 2 in lunar orbit

The Chandrayaan 2 spacecraft entered into an orbit around the Moon on August 20, 2019 at 09:02 AM (IST).

This was a result of a lunar orbit insertion (LOI) manoeuvre the spacecraft performed that lasted about 1738 seconds. The spacecraft was in Earth orbit and used it’s gravity to be propelled towards the Moon. As the spacecraft reached close to the Moon it used its on-board motor to perform a breaking to decrease its speed (this was demonstrated in Mission Mangal) and allowed itself to be captured by the Moon’s gravitational force.

The spacecraft entered into a 114 km x 18,072 km orbit around the Moon. This means that the spacecraft’s closest distance from the Moon (caller perilune) is 114 km and it’s farthest distance (called the apolune) is 18,072 km. The next day it performed another similar manoeuvre to reduce its speed and moved into an 118 km x 4,412 km orbit. This is the opposite of what it did in Earth orbit and will continue till it achieves a circular orbit of 100 km.

Image from the ISRO Launch Kit for Chandrayaan 2 which shows the mission sequence.
The Chandrayaan 2 spacecraft is now in its Lunar Bound Phase. Image: ISRO Launch Kit
Moon as viewed by Chandrayaan-2 LI4 Camera on 21 August 2019 19:03 UT
Moon as viewed by Chandrayaan-2 LI4 Camera on 21 August 2019 19:03 UT

Today, ISRO released pictures taken by the LI4 camera on board the Vikram lander of the Chandrayaan 2 spacecraft. LI4 probably stands for Landing Imager 4. It should be one of the cameras on the lander that would be used to guide the lander to the surface of the Moon.

The next manoeuvre is slated for August 28, early in the morning. You can follow the updates of Chandrayaan 2 directly from the ISRO website page.

Chandrayaan 2 on the way to the Moon

Chandrayaan 2, India’s second mission to the Moon lifted off from Sriharikota on July 22, 2019. The spacecraft was launched on board India’s GSLV Mk-3 rocket on it’s maiden non-development flight.

Photograph of the launch of the GSLV Mk-3 with the Chandrayaan 2 spacecraft by ISRO.
GSLV Mk 3 lifts-off with Chandrayaan 2. Image Courtesy: ISRO

It came after a launch scrub surrounding which there was lack of information and a lot of speculation. I watched the launch with my grandmother in Mumbai.

Since the launch, the spacecraft which currently has an orbiter and lander attached to each other performed 5 orbit raising manoeuvres on the way to the Moon.

India adopted this gradual orbit raising manoeuvre in order to balance the limitation of the spacecraft and the launch vehicle. A lower mass of the spacecraft would enable the launch vehicle to place the spacecraft into lunar orbiter but it would then not be able to carry any meaningful payload. The launch vehicle had only enough power to place Chandrayaan 2 in a geosynchronous transfer orbit.

Image of the Earth taken by LI4 camera on board the lander on Chandrayaan 2.
Image of Earth taken by the LI 4 camera on board Chandrayaan 2. Image Courtesy: ISRO

After the 5th orbit raising manoeuvre, the spacecraft will push off towards the Moon called Trans Lunar Insertion on August 14. Afterwards, the spacecraft will perform one more burn called the Lunar Orbit Insertion on August 20 that will let the spacecraft be captured by Moon’s gravity.

NISAR will look at the Antarctic

Alexandra Witze writes for Nature about a decision relating to NASA and ISRO joint mission called NASA ISRO Synthetic Aperture Radar (NISAR) decision to point at the Antarctic rather than the Arctic.

The decision is based on the fact that the Europe’s Sentinel satellite is covering the Arctic region. Also, SAR satellites are built such that they point either to the North or the South pole. Hence a call was taken on which Pole the NISAR would be facing.

The South Asia Satellite

The ISRO will launch the GSLV tomorrow carrying the South Asian Satellite on board. ISRO calls it the GSAT-9. It will carry Indian transponders that will be used by India, Nepal, Bangladesh, Bhutan, Sri Lanka and the Maldives. The Wire has a short video describing the significance of the launch and some prior history.

GSAT-9 seen with the two halves of the payload fairing of the GSLV-F09. Image Credit: ISRO

I think this launch will be important for India for two things. One is to prove, further, the reliability of the GSLV as a launch vehicle capable of regularly delivering communication satellites into orbit. This improves with each launch. As this reliability improves, it brings in business in communication satellite launches as well as reduces India’s dependence on foreign launch vehicles. The second is to improve availability of transponders for users on the ground. Indian transponders can thence be leased and commercialized after meeting India’s requirements.

It would be interesting to see if the use of the transponders by some of our neighboring countries provides them with sufficiently good experience that they will continue using Indian transponders or even ask for multiple transponders. This would make it important again to improve the reliability of the GSLV and the GSLV Mk-III to put enough communication satellites into orbit to service these future requirements. Could then India wean off South East Asian countries from American and European transponders to Indian ones?

Interestingly, this satellite also carries with it an electric propulsion experiment. This satellite is expected to stay in orbit for 12 years. Communication satellites usually  last around 10 years. They have to carry as much fuel for what is known as station keeping. The satellites begin to drift from orbit like kites that we fly. We tug at the kite to keep it at one place and prevent it from drifting too far away. The satellite has no strings attached and hence the satellite will have to use fuel on-board to reach its orbit as well as to stay there.

Using electric propulsion completely for doing station keeping would reduce the amount of fuel the satellite would have to carry. This means we can add more transponders which in turn would mean fewer satellites could meet the requirements. But, this is an experiment and hence ISRO is still carrying the fuel it normally would had the electric propulsion system had not been there. I am also delighted to hear that the GSAT-20 mission flying next year will also carry an electric propulsion system on board. The lessons we learn from the experiment on the GSAT-9 would be incorporated.