Indian Space Program: News & Discussion - Sept 2016

Varoon Shekhar · Post by **Varoon Shekhar** » 12 Jan 2017 18:07

[quote="disha"]

http://www.newindianexpress.com/cities/ ... 56290.html

The delay of the GSLV Mark 3 to March is a bit disappointing. But, on sober reflection, one can see that it is a very major and sophisticated mission, and they want to take no chances.

However, look at a couple of the comments to the Express article. My goodness, are some Indians that cynical and jaded. It's one thing to whine about delays( like I do) but to accuse ISRO of hype and being very slow, with "only" 5-6 missions a year, that is awful. Do these people know the background of the space programme or of India itself, economically and industrially? And it's not going to be 'only' 5-6 a year, already last year it was 7, and in the coming year probably 8-10. What do these people expect?

Gagan · Post by **Gagan** » 12 Jan 2017 18:28

These guys are chronic whiners. They wake up in the morning and start whining about how the water is not hot enough, or the tea is cold, and they whine all day long until they go to sleep.
They're probably complaining even in their dreams...
Frustrated keyboard warriors!

None of these newbie space agencies in the US has half the launch rate as ISRO does, and these guys have unrestricted funding and tech support from ex NASA, not to mention geographic proximity to NASA and all manner of test facilities and industry support.

ISRO, hemmed in as it is, with one hand tied behind their back, given the sarkari nature of its organization and funding, is doing just fine! They are a Icon for all nations to follow as an example!

Cybaru · Post by **Cybaru** » 12 Jan 2017 19:03

+1

Gagan wrote:These guys are chronic whiners. They wake up in the morning and start whining about how the water is not hot enough, or the tea is cold, and they whine all day long until they go to sleep.
They're probably complaining even in their dreams...
Frustrated keyboard warriors!

None of these newbie space agencies in the US has half the launch rate as ISRO does, and these guys have unrestricted funding and tech support from ex NASA, not to mention geographic proximity to NASA and all manner of test facilities and industry support.

ISRO, hemmed in as it is, with one hand tied behind their back, given the sarkari nature of its organization and funding, is doing just fine! They are a Icon for all nations to follow as an example!

prasannasimha · Post by **prasannasimha** » 12 Jan 2017 20:50

Actually I have seen ISRO scientists slog it day in and out during launch campaigns. This is a high risk and high stakes industry and it is easy to criticize but one error and millions of rupees worth of equipment will literally be blown into the air.

disha · Post by **disha** » 13 Jan 2017 08:07

People who say that ISRO scientists work at "Sarkari Pace" should actually read Wings of Fire*., where people put in their lives at stake to get the mission going. Even recently., when the cyclone passed near SHAR - a general holiday was declared and some of the "sarkari types" still showed up for work.

DukhiAtma's who criticize ISRO and blame all societal evils on them will eternally whine. At the same time., think about it - the DukhiAtma's at least think that we as Indians have the potential to reach or even get ahead of other nations. So their whine is about what they perceive is achievable and what they see as achieved. Having said that., the dukhiatma's should also realize that forever whining actually saps the energy even from people who are motivated to bring a positive change and leads to the same negative spiral they are complaining about.

In the meantime., here is a good article from swarajyamag** http://swarajyamag.com/ideas/a-new-fron ... -programme

*There is a side anecdote there., I bet that Abdul Kalam'ji and his colleague ran faster than Usain Bolt on that day. All the newbies should be made to dig out that anecdote from Wings of Fire and recount us the tale and tell us why we think Kalam'ji bolted that fast!

** Some forumites (including me) will still complain that the article is too simplistic., but remember the audience is not as well informed as an avg BRFite.

disha · Post by **disha** » 13 Jan 2017 08:16

Varoon'ji., you are not whining - you are expressing your disappointment over delays. Which is just fine.

All I am trying to do is put a different perspective on "wait"., think about it - I have been waiting for GSLV-Mk II since 1980s and for GSLV Mk III since early 2000s.

Bheeshma · Post by **Bheeshma** » 13 Jan 2017 09:03

Really? PSLV was only launched in 1993 and you were already waiting for GSLV Mk-2

. Talk about being optimistic!!

From wiki.

The Geosynchronous Satellite Launch Vehicle (GSLV) project was initiated in 1990 with the objective of acquiring an Indian launch capability for geosynchronous satellites.[3] India has depended on the United States and Europe for the launch of INSAT class of satellites.[4

Sid · Post by **Sid** » 13 Jan 2017 09:36

Elon Musk's chart on rocket performance from across the world. In the long run this is what we should set as our target.

SaraLax · Post by **SaraLax** » 13 Jan 2017 13:45

Sid wrote:Elon Musk's chart on rocket performance from across the world. In the long run this is what we should set as our target.

Image Snipped Out by me

Let's see how Elon Musk's/SpaceX's FALCON-9 (heavily supported by funding+technology_expertise+skilled_workers from NASA) is going to come back to launch activity in the coming day or two after that spectacular launch site destruction many months before.

nirav · Post by **nirav** » 13 Jan 2017 16:37

Who is musk and why should our country peg it's space program on his rocket performance chart ?

We have our own unique needs and capabilities, our space program is thus based on our requirements and capacity.

The GSLV mk3 and its further evolutions + our shuttle are our stated goals.. we are chugging along nicely.

Musk could probably land a rocket on a Tesla.doesnt mean we gotta do it too.

Bheeshma ji gets the ACP Pradyuman award

SaiK · Post by **SaiK** » 15 Jan 2017 01:09

http://www.thenewsminute.com/article/fl ... -map-55664

check out the great video in the link.
-------------------

musk-eteer can spoil ISRO market. other than that, I don't any relevance to this dhaaga.
10 sats in one launch.. no cell phone tower ever needed to be on cellular network. think about musk!

disha · Post by **disha** » 15 Jan 2017 01:30

Sid wrote:Elon Musk's chart on rocket performance from across the world. In the long run this is what we should set as our target.

Why?

disha · Post by **disha** » 15 Jan 2017 01:39

Bheeshma wrote:Really? PSLV was only launched in 1993 and you were already waiting for GSLV Mk-2 . Talk about being optimistic!!

From wiki.

The Geosynchronous Satellite Launch Vehicle (GSLV) project was initiated in 1990 with the objective of acquiring an Indian launch capability for geosynchronous satellites.[3] India has depended on the United States and Europe for the launch of INSAT class of satellites.[4

The original plan for Geo-sync rockets vehicles were called out in 1984 itself. It was in 1983-84., the roadmap was spelled out after/during SLV. Viz - ASLV, PSLV followed by GSLV.

SLV/ASLV were more like staging projects - SLV was to build/understand various rocket propulsions and staging. ASLV tested out the crucial closed-loop guidance system. PSLV was the goal for EO and GSLV was the goal for Tele-Comm Sats. It was clear that India needed both EO and Tele-Comm sats and different rockets were needed to orbit them. So the vision and road-map was very much there.

What you mention in wiki & quote in reference is the 'official' initiation of the GSLV project not the roadmap. Wiki is wrong., since it goes in this instance by a sarkaari document. GOI/ISRO has this classic case where ISRO puts up a proof-of-concept and initiates work and then GOI gets confident and sanctions the project officially. Till then, ISRO funds it from its own resources. Take a look at RLV for eg. If tomorrow GOI sanctions the "reusable space plane" project., it does not mean that the space plane was never envisioned before., it basically means that the space plane was envisioned but the requirements and the goals were firmed up prior to pre-project and GOI sanctioned funds for undertaking that project thus initiating that project. So in future when you are old and mention that Space Plane was envisioned say in 2000s., some future bheesma will "moogle" up "ziki" and will correct you and point out that the space plane was initiated only in 2020s.

So yes., in 1983/84 after the launch of SLV - I was scouring papers and the roadmap was clearly spelt out - SLV/ASLV/PSLV and GSLV. GSLV being the Amrutam after the manthanam.

Added later:

Check out the vision of stalwarts Dr. Sarabhai and Dr. Dhawan. Concentrate when Dr. Sarabhai mentions Tele-Comm sats.

Why is ISRO successful? Since it was given vision, a plan, a roadmap spanning several decades to follow through. The rest is initiation of projects at right points.

So Bheesma'ji., before you go ahead and ridicule with some inanities from wiki., do note that wiki is not the only source. And also buy this book https://www.amazon.co.uk/Vikram-Sarabha ... B004EQSV6Q

The second book you must buy is Amrita Shah's on Sarabhai. It clearly spells out the vision of Sarabhai and how he envisaged different areas like launch vehicles, satellite centers, tracking and monitoring network etc. Here is the link on the author of the book http://oneindiaonepeople.com/unlike-mos ... discovery/

My suggestion to you Bheesma'ji is to actually read the above two books and improve the content of the wikis.

And also can you scour this site http://www.thebetterindia.com/74283/fir ... dul-kalam/., there is the photo of the first nike-apache launch on the hydraulic crane. That photo is priceless.

Also Bheesma'ji - since you have great search skills and going to wiki to point us out when GSLV program was initiated., can you also get me the pages 79 onwards from this DRDO PDF (I am able to find only first 7 pages)

http://www.drdo.gov.in/drdo/pub/monogra ... t-2014.pdf

Bheesma'ji - you surely must have read the wings of fire by APJ Kalam. If not, well it is a mandatory read. However one more book you must read (and should be made mandatory for posters on this thread) is the book by Prof. UR Rao.

Please check out that book., since in that book this is what Prof. UR Rao mentions this (from review of his book by Hindu newspaper):

...INSAT dominated the space programme until 1994. At the same time, even as development of the PSLV programme was underway, a multitude of reasons were coming together to press for developing the next generation of launch vehicles. The baseline requirement that fixed the capacity of the GSLV was the government’s approval for ISRO to build the INSAT-2 series of satellites, each weighing over two tonnes — well beyond the PSLV’s capacity of 1.4.

At this juncture, Prof. Rao brings to light an interesting detail. While ISRO was working on the GSLV in 1988, the General Dynamics Company, USA, approached it with an offer to sell two RL-10 cryogenic engines at $800 million. The deal didn’t go through, including technology transfer, as the cost was prohibitive. A similar thing happened between ISRO and Arianespace in 1989, which had in fact quoted $1,200 million. It was then that ISRO took the “bold decision” to build a 12-tonne cryogenic engine of its own, according to Prof. Rao, demonstrating the extent of our self-reliance 24 years ago.

Please re-read it and check the date for GSLV.

Lilo · Post by **Lilo** » 15 Jan 2017 02:26

SaiK wrote:http://www.thenewsminute.com/article/fl ... -map-55664

check out the great video in the link.
-------------------

musk-eteer can spoil ISRO market. other than that, I don't any relevance to this dhaaga.
10 sats in one launch.. no cell phone tower ever needed to be on cellular network. think about musk!

https://www.youtube.com/watch?v=k6E7qGhOGCA

Lilo · Post by **Lilo** » 15 Jan 2017 02:28

Hope this is not posted earlier

India's Mars Orbiter Mission Has a Methane Problem
By Irene Klotz, Seeker | December 8, 2016

More than two years after its pioneering Mars Orbiter Mission (MOM) reached the red planet, the Indian Space Research Organization has yet to release highly anticipated measurements of atmospheric methane, a gas which on Earth is strongly tied to life.

Seeker has learned that the data will never come, due to a flaw in the sensor design.

"They did not design this properly for the detection of methane on Mars," Michael Mumma, senior scientist at NASA's Goddard Space Flight Center, told Seeker.

In 2003, Mumma led a team that made the first definitive measurements of methane on Mars using an infrared telescope in Hawaii. The methane, which appeared in plumes over specific regions of Mars, reached a maximum density of about 60 parts per billion.

"The (MOM) instrument is beautifully engineered, but not for the methane task. It has other value, but unfortunately they will not be able to provide measurements of methane at the levels needed to sample even the plumes we saw," Mumma said.

The problem has to do with how the instrument collects and processes detections of methane in the atmosphere, a technique known as spectroscopy.

"Imagine that you hold your hand in front of you and extend your four fingers … Suppose that each (finger) represents a methane line. What they have is a spectrometer that can be shifted to … sample each one of the four fingers and then they have a second one that samples the region between the fingers.

"The trouble is they don't actually send back the spectra. What they send back is the two numbers — the sum of the fingers measured by the first channel and the sum of gaps measured by the second channel — and then they take a difference of those two numbers and they think that that's going to be the methane signal," Mumma said.

"The problem, of course, is that when you have other spectral lines … like carbon dioxide lines which vary widely with temperature in terms of their intensity, then those two numbers … don't represent methane alone. The net effect is that there is no way that one can back out those two signals in order to retrieve a methane signal," he said.

"It's really unfortunate because they succeeded so spectacularly well in placing the spacecraft into orbit at all, which was the major achievement for the first try," he added. "But the reality is we won't seeing any detections of methane from the Mars methane sensor on MOM."

Mumma and colleague Geronimo Villanueva, also at Goddard, analyzed the MOM methane instrument design as part of NASA's widening partnership with ISRO.

Their findings were presented to the Indian space agency ISRO in February.

"I believe the resolution is that the Indians now agree that their methane sensor is better used for other purposes, so they are now calling this an albedo mapper and measuring reflected sunlight. It does that, and it does that well," Mumma said.

"The engineers know how to build a good instrument. That's not the issue. The problem is they didn't have the scientific guidance needed to tell them exactly what they needed to do," he said.

Seetha Somasundaram, with ISRO's Satellite Center which designed the instrument, declined to comment and referred Seeker to ISRO spokesman Deviprasad Karnik. Karnik did not responded to requests for comment.

Mumma and other scientists are now pinning their hopes on getting Mars methane measurements from Europe's newly arrived Trace Gas Orbiter.

Update (2 p.m. ET): ISRO spokesman Deviprasad Karnik emailed the following statement to Seeker: "The Methane sensor onboard MOM has been sending data about atmospheric Methane of planet MARS and the data received is under analysis." Karnik did not address questions about scientists' ability to ferret out methane signals from the data.

Originally published on Seeker.

SriKumar · Post by **SriKumar** » 15 Jan 2017 04:04

Varoon Shekhar wrote: However, look at a couple of the comments to the Express article. My goodness, are some Indians that cynical and jaded. It's one thing to whine about delays( like I do) but to accuse ISRO of hype and being very slow, with "only" 5-6 missions a year, that is awful. Do these people know the background of the space programme or of India itself, economically and industrially?

A majority have no clue of what it takes to get some hardware up there, and in a reliable fashion. The PM ghazis probably think it is like launching the next version of a software (Windows ver. 785) with bug fixes to come later

. The same gang, if there is a problem with the launch, will go off on how 'ISRO cannot even launch a rocket etc...'.

bharats · Post by **bharats** » 15 Jan 2017 10:56

Lilo wrote:Hope this is not posted earlier
India's Mars Orbiter Mission Has a Methane Problem
By Irene Klotz, Seeker | December 8, 2016
...............
"They did not design this properly for the detection of methane on Mars," Michael Mumma, senior scientist at NASA's Goddard Space Flight Center, told Seeker.
................
"The engineers know how to build a good instrument. That's not the issue. The problem is they didn't have the scientific guidance needed to tell them exactly what they needed to do," he said.
Seetha Somasundaram, with ISRO's Satellite Center which designed the instrument, declined to comment and referred Seeker to ISRO spokesman Deviprasad Karnik. Karnik did not responded to requests for comment.
..............
Originally published on Seeker.

If Seeker assessment is true, then it's alarming not because the Methane Sensor for Mars (MSM) instrument has not met its primary objective and failing, but the scientific advisory has failed in their roles, possibly reflecting the current scientific research state in INDIA. The time has come for GOI to invest heavily in scientific research and enhance the quality of thoughts and innovation along with engineering.

Supratik · Post by **Supratik** » 15 Jan 2017 12:36

Please wait before passing judgement. It is coming from a competitor.

disha · Post by **disha** » 15 Jan 2017 23:36

bharats wrote: If Seeker assessment is true, then it's alarming not because the Methane Sensor for Mars (MSM) instrument has not met its primary objective and failing, but the scientific advisory has failed in their roles, possibly reflecting the current scientific research state in INDIA. The time has come for GOI to invest heavily in scientific research and enhance the quality of thoughts and innovation along with engineering.

This should be in "GREAT" post thread. Since in one 3-line paragraph post., we are finding the cause [bolded], analysis [underlined]and solution [italics] to the problems faced by ISRO in general and India in particular.

Neshant · Post by **Neshant** » 15 Jan 2017 23:51

Supratik wrote:Please wait before passing judgement. It is coming from a competitor.

Thats what I was thinking.

Let's wait for the official pronouncement.

SriKumar · Post by **SriKumar** » 15 Jan 2017 23:55

disha wrote: Since in one 3-line paragraph post., we are finding the cause [bolded], analysis [underlined]and solution [italics] to the problems faced by ISRO in general and India in particular.

^^^Indeed. It seems quite a leap going from an (undetailed) comment in a news article to some 'advisory' group 'failed in their roles' to 'investing in scientific research'. Surprising.
On an un-related note, it is curious how Dr. Mumma got to know of the information of the specific problem in a specific instrument (which ISRO does not seem to have made public). MOM was a solely Indian effort and no external agencies were involved as far as I know. And this is the first time I am seeing a the name of designer of a specific instrument on a satellite mentioned in an article- very strange. I cant image ISRO released it, but maybe it did.
Unrelated but I also recall that MOM was executed in a highly, highly compressed time schedule.

Varoon Shekhar · Post by **Varoon Shekhar** » 16 Jan 2017 20:35

http://www.isro.gov.in/high-altitude-fl ... ccessfully

This is on ISRO's site today, but it is not clear whether the test of the C-20 was done in the last few days, or many months ago. Perhaps some ongoing mini-tests. Anyway, let's hope that 'early 2017' means March.

prasannasimha · Post by **prasannasimha** » 16 Jan 2017 23:20

Did you know that the vacuum seal of a high altitude test facility is maintained by a shockwave !!

AdityaM · Post by **AdityaM** » 17 Jan 2017 16:12

prasannasimha wrote:Did you know that the vacuum seal of a high altitude test facility is maintained by a shockwave !!

in simpler english this would mean what?

jayasimha · Post by **jayasimha** » 18 Jan 2017 16:11

http://pib.nic.in/newsite/PrintRelease. ... lid=157460

Print ReleasePrintXClose
Press Information Bureau
Government of India
Cabinet
18-January-2017 15:45 IST
Cabinet apprised of the MoU between the Indian Space Research Organisation (ISRO) and the Japanese Aerospace Exploration Agency (JAXA) for cooperation in the field of outer space

The Union Cabinet chaired by the Prime Minister Shri Narendra Modi has been apprised of the Memorandum of Understanding (MoU) signed on November 11, 2016 at Tokyo, Japan between the Indian Space Research Organisation (ISRO) and the Japanese Aerospace Exploration Agency (JAXA) for cooperation in the field of outer space.

The purpose of this MoU is to pursue future cooperative activities in the exploration and use of outer space exclusively for peaceful purposes in accordance with the laws and regulations applicable in each country and their international obligations.

This MoU provides scope for pursuing cooperation in various areas of space science technology and applications including: eearth observation, satellite communication and navigation; exploration and space sciences; Research and development (space systems and space technology); and Space industry promotion.

ISRO and JAXA will bear the costs of their respective activities under this Memorandum, unless they decide otherwise in writing. Ability to fulfil their respective roles and activities under this Memorandum and its relevant separate Implementation Arrangement is subject to their respective funding procedures, the availability of appropriated funds and their respective national laws.

Framework MoU would lead to joint activity in the field of application of space technologies for the benefit of humanity. Thus all sections and regions of the country will get benefited.

Background:

India and Japan pursue space cooperation for more than 5 decades and carried out studies in the field of atmospheric study, observation of universe and scientific investigation in remote sensing. With the formation of JAXA in 2003, an "arrangement concerning the considerations of potential future cooperation in the field of outer space" was signed in October 2005 between ISRO/ Department of Space (DOS) and JAXA. Subsequently both agencies have signed cooperative documents addressing lunar exploration, satellite navigation, X-ray astronomy and Asia Pacific Regional Space Agency Forum (APRSAF).

During the ISRO-JAXA bilateral meeting held at New Delhi on April 05, 2016, both sides stressed the need for updating the contents of '2005 Arrangement' with enhanced scope of cooperation. Accordingly, both sides have arrived at the draft of new 'Memorandum of Understanding (MoU) between ISRO and JAXA concerning cooperation in the field of outer space’ and got it signed on November 11, 2016 at Tokyo during the visit of Prime Minister of India to Japan.

*****
AKT/VBA/SH

PratikDas · Post by **PratikDas** » 20 Jan 2017 01:21

Click for a very high res image of the CE 20 at ISRO's High Altitude Test Facility

SSridhar · Post by **SSridhar** » 20 Jan 2017 08:39

Milestone in cryogenic engine test paves way for GSLV-MkIII - Madhumathi D.S., The Hindu

A milestone crossed in the making of a new cryogenic rocket engine set the stage for the first flight of the country’s most powerful satellite launcher to date, the GSLV-Mark III. The cryogenic stage and the entire launch vehicle’s readiness is closer to fruition after the engine, technically called CE20, passed the ‘high altitude flight acceptance test’ lasting about 25 seconds at Mahendragiri in mid-December.

The Indian Space Research Organisation (ISRO) plans to fly its new launch vehicle powered by this new engine around March, and send the 3,200 kg GSAT-19 communication satellite to space on it. The launch was earlier slated for December 2016. MkIII, when it completes trials and commences functioning in the coming years, will double ISRO’s lifting power for communications satellites to 4,000 kilos.

Vital stage

In a few days from now, the rocket’s complete cryogenic third stage, replete with fuel tanks and systems built around the engine, will undergo its qualifying test, S. Somanath, Director of ISRO’s Liquid Propulsion Systems Centre (LPSC), Thiruvananthapuram, told The Hindu .

LPSC has designed and developed the CE20 engine. We are assembling the entire cryogenic stage, which is ready for flight. It will be sent to Sriharikota in a month’s time,” he said.

The cryogenic stage is vital for a GSLV rocket as it gets its final and biggest push in space from this stage; it can take a big communications satellite to higher reaches of 36,000 km above ground. The C25 cryogenic stage was approved at an estimated Rs. 600 crore as part of the overall Rs. 2,500-crore MkIII launcher project.

“Realising the CE20 engine was our target in order to achieve India’s capability to lift a four-tonne satellite to GTO (geostationary transfer orbit, around 36,000 km high),” Mr. Somanath said.

“We have been longing for this for a few years. MkIII will be the future work horse after the PSLV,” he said.

prasannasimha · Post by **prasannasimha** » 20 Jan 2017 09:12

AdityaM wrote:
prasannasimha wrote:Did you know that the vacuum seal of a high altitude test facility is maintained by a shockwave !!
in simpler english this would mean what?

I was always wondering how they could test an engine in vacuum when the exhaust entering the chamber would "break " the vacuum and the exhaust has to go somewhere ie an outlet. The HAT facility revs up to create the vacuum but on firing the engine the shock wave travels along a long outlet and "seals " the exit maintaining the gradient between the atmosphere and test chamber allowing exhaust to exit bit maintaining the vacuum seal if the chamber. Interesting method.

Nick_S · Post by **Nick_S** » 22 Jan 2017 20:39

Fly your name to the moon for Rs 500
http://www.business-standard.com/articl ... 656_1.html

If you pay Rs 500 to the first private moon mission in the country, Team Indus, your name could be etched on an object travelling to the celestial satellite next year. Team Indus is looking to raise money through crowdfunding for its mission. Those contributing would have their names written on an aluminium block that will accompany the mission’s rover to the moon, reaching on January 26, 2018. The initiative, to be launched next month, is looking to raise up to $10 million by getting 1.4 million citizens to back the mission

SaiK · Post by **SaiK** » 22 Jan 2017 21:17

can someone make a simulation based on this information? we had one done for MOM.

http://www.thehindu.com/sci-tech/scienc ... 075073.ece

prasannasimha · Post by **prasannasimha** » 24 Jan 2017 00:09

http://www.isro.gov.in/long-eclipse-avo ... spacecraft

An orbital manoeuvres was performed on Mars Orbiter Mission (MOM) spacecraft to avoid the impending long eclipse duration for the satellite. The duration of the eclipse would have been as long as 8 hours in the coming days. As the satellite battery is designed to handle an eclipse duration of only about 1 Hour 40 minutes, a longer eclipse would have drained the battery beyond the safe limit. The manoeuvres performed on January 17, 2017 brought down the eclipse duration to zero during this long eclipse period.

On the Evening of January 17, all the eight numbers of 22N thrusters were fired for a duration of 431 seconds, achieving a velocity difference of 97.5 m/s. This has resulted in a new orbit for the MOM spacecraft, which completely avoids eclipse up to September 2017. About 20 kg propellant was consumed for this manoeuvres leaving another 13 kg of propellant for its further mission life.

The spacecraft health is normal. The next long eclipse period for MOM is expected in the year 2020.

Varoon Shekhar · Post by **Varoon Shekhar** » 24 Jan 2017 01:08

Wow so it's in a different orbit now. Any idea whether the pictures will be different? Type, resolution, location etc

Amber G. · Post by **Amber G.** » 24 Jan 2017 12:39

^^^^ With respect to understanding change in orbits, one very nice exercise I put (see note **) is quite educational for understanding.
(There was lot of discussion, so I put up some very detailed comments). Worth going through.

Note: Original problem at :
viewtopic.php?f=3&t=6652&p=2037281&hilit=orbit#p2036920

Lot of discussion follows and detail analysis is at :
viewtopic.php?f=3&t=6652&p=2037787&hilit=orbit#p2037787

This may add to some understanding -- how 103 satallites could have different orbits or what is involved in Mangalyaan's orbit changes.

gashish · Post by **gashish** » 25 Jan 2017 06:10

Moon Beer? Brewing Experiment Short-Listed for Indian Lunar Lander

Ashokk · Post by **Ashokk** » 25 Jan 2017 18:31

India's Swadeshi GPS Develops A Problem, But Remains Functional

India's home-made navigational system, named NAVIC by Prime Minister Narendra Modi, has developed a technical problem. One of the seven satellites in the Indian version of the American Global Positioning System or GPS is malfunctioning, as a result of which it's not visible. The seven satellites together provide strategic services, the last of them was launched in April last year. Despite the flaw, the Indian Regional Navigation Satellite System is still functional.

"The on-board atomic clock has developed a problem and we are trying to revive it," said Dr Kiran Kumar, Chairman of ISRO or the Indian Space Research Organization, to NDTV.

Atomic clocks are used for precision time-keeping; India had imported these for the constellation of seven satellites in its GPS.

In a similar fashion, atomic clocks on Europe's satellite navigation system Galileo have also been failing, leaving half of its 18 satellites in orbit without clocks. When the time signal is missing, getting true positional accuracy is eroded.

India has spent close to 1,700 crores on this navigation system, named NAVIC or Navigation with Indian Constellation.

The NAVIC system is akin to the American Global Positioning System (GPS) but it is regional in nature covering the Indian region and ISRO claims it gives a much higher accuracy for military users than other systems like it.

raj-senthil · Post by **raj-senthil** » 26 Jan 2017 23:16

ISRO Successfully Tests C25 Cryogenic Upper Stage of GSLV MkIII

Indian Space Research Organisation (ISRO) successfully ground tested its indigenously developed Cryogenic Upper Stage for GSLV MkIII on January 25, 2017. The cryogenic stage designated as C25 was tested for a duration of 50 seconds at ISRO Propulsion Complex (IPRC) in Mahendragiri demonstrating all the stage operations. The performance of the Stage during the test was as predicted. This is the first test in a series of two tests. The next test is planned for flight duration of 640 seconds.

The 50 second test is a significant milestone in the development of indigenous cryogenic propulsion technology. The successful hot test of the stage in the first attempt itself demonstrates ISRO’s ability to work in new areas like cryogenic technology.

The development of C25 cryogenic stage began with the approval of GSLV MKIII, the next generation launch vehicle of ISRO, capable of launching 4 ton class spacecraft in Geosynchronous Transfer Orbit (GTO). The vehicle consists of two solid strap-on motors (S200), one earth storable liquid core stage (L110) and the cryogenic stage upper stage (C25).

The C25 stage was conceptualised, designed and realised by Liquid Propulsion Systems Centre (LPSC), ISRO’s lead Centre for Propulsion, with support from various System Development Agencies from other three Centres of ISRO – Vikram Sarabhai Space Centre (VSSC), ISRO Propulsion Complex (IPRC) and Sathish Dhawan Space Centre (SDSC) SHAR. The fabrication of various sub-systems of the engine and the stage was carried out through Indian Industries.

The C25 stage is the most powerful upper stage developed by ISRO and uses Liquid Oxygen (LOX) and Liquid Hydrogen (LH2) propellant combination. The stage carries 27.8 tons of propellants loaded in two independent tanks.

Development of a cryogenic stage has unique design challenges, with liquid Hydrogen stored at -253 deg C and liquid Oxygen stored at -195 deg C in its tanks. To store these cryogenic fluids, special multi-layer insulation is provided for the tanks and other structures.

The first flight stage for GSLV MkIII-D1 mission is in advanced stage of realisation. The flight engine has been successfully tested in the High Altitude Test (HAT) facility and integrated with the flight stage.

suryag · Post by **suryag** » 26 Jan 2017 23:41

what is the difference between CE20 and c25

Gagan · Post by **Gagan** » 27 Jan 2017 01:43

CE-20 is the cryo engine. Note the E present. This generates approx 200 KN thrust. Again note ISRO designation 20=200kN thrust. CE-7.5 generates 75kN thrust & powers the 3rd stage of the gslv mk2

C-25 is the entire rocket stage which consists of the CE-20 engine + liquid Hydrogen and Liquid Oxygen fuel tanks in a special thermal proofed casing

C-25 will be the 3rd stage on the Mk 3

Indranil · Post by **Indranil** » 27 Jan 2017 01:58

The C25 stage can be read as cryo stage with approximately 25 Ton propellant mass.

The other acronyms are SC (Semi cryo), S (solid) and L (liquid).

So L110 is a liquid stage with approximately 110 Ton propellant mass, and S200 is a solid stage with approximately 200 Ton of propellant mass.

disha · Post by **disha** » 28 Jan 2017 02:04

suryag wrote:what is the difference between CE20 and c25

A subtle question is why the two designations?

CE 20 as has been pointed out produces 200 kN thrust while the C25 is a stage with 25 tonnes of propellant using the CE 20 engine.

Tomorrow, ISRO can come up with a C50 or C75 or C100 stage with equivalent tons of propellant but still use the CE 20 engine. It may even choose to cluster four or five CE 20 engines and put it together in a C125 stage.

This designations are to differentiate between the engine and the stage. There is a separate engineering required for stage., and that is why even when the engines were successfully tested we had to wait for the stage designs to come through. Think about it., if the stage is rocketed at 30 m/s., then the inter-stage trusses supporting it will be feeling some 75 tonnes of weight for 25 tonne stage. And hence has to be engineered appropriately.