Indian Space Program Discussion

jaladipc · Post by **jaladipc** » 07 Apr 2010 21:29

I do remember that an ISRO official saying that 2 ion thrusters were tested earlier on an experimental sat( for N-S station keeping) along side conventional thrusters.

Katare · Post by **Katare** » 07 Apr 2010 23:24

nukavarapu wrote:^^^

Mr. Veeraraghavan said three highlights of the GSAT-4 were its communication system in Ka-band; its GAGAN payload which would help in the landing accuracy of commercial aircraft at airports in India; and the satellite's electric propulsion system which would help in correcting the spacecraft's attitude and ensuring a longer life in orbit.
Am I day dreaming? Is Mr. Veeraraghavan pointing to ION Thruster in GSAT-4 ??? If thats true, its gonna be amazing. Way to go ISRO !!!

Electric prop is old and useful tech but doesn't qualify for "dreaming" category......

Varoon Shekhar · Post by **Varoon Shekhar** » 08 Apr 2010 00:00

Thanks Krish. BTW, is it correct to assume that the Tauvex will not be part of the payloads on board GSAT-4, and hence, when will that be launched, on a future GSLV?

I found this off another message board, quite humorous. Amazingly, a few readers took the remark seriously, and wrote incensed replies! It looks like either some Indians don't appreciate sarcasm, or that they have seen so many of these "Doesn't India have other priorities" type cynicism, that they reflexively respond to each one in the same way!

"This is a waste. Why is the government stopping the building of Mayawati statues and launching rockets? After the rocket is launched you cannot see it anymore. If you build statues for Mayawati, we can see it everyday. Please close down ISRO so that funds can be allotted."

arun · Post by **arun** » 08 Apr 2010 07:11

^^^ it would be correct to assume that Tauvex will not be a part of the GSLV D3 payload.

PTI via Deccan Herald:

ISRO receives flak for delay in launching Israeli satellite

disha · Post by **disha** » 08 Apr 2010 08:22

arun wrote:^^^ it would be correct to assume that Tauvex will not be a part of the GSLV D3 payload.

PTI via Deccan Herald:

ISRO receives flak for delay in launching Israeli satellite

Too much Rona & Dhona (R&Dh) by the DDM reporter.

First of all GSLV D3 is a development vehicle and has not been commercialized as the name suggests. So there is no point in putting a "commercial" payload on a development flight. Second there are questions raised by ISRO itself on the need for TAUVEX being at geo-stationary orbit. Note that ISRO has more experience operating various satellites in various orbits. So if they have concerns, they have. Either the TAUVEX proj. mgmt. understands this and addresses it or complains about it. Complaining about it will not get them anywhere. They can do more Rona & Dhona, if TAUVEX needs to be in Geo orbit and when GSLV Cx has a slot it will take it there. If it needs to be in other orbit and if PSLV suffices it will be that way.

K Mehta · Post by **K Mehta** » 08 Apr 2010 14:23

ISRO saga forward-Technological Dimension Dr K Radhakrishnan
ISRO till today has carried out 54 Indian satellite missions
21 Indian satellites are currently in orbit
Launched 22 foreign satellites

All this was done in 3% of NASA budget, 12% of ESA budget and 1/3 budget of Chinese space agency.
Main Objectives of the space program
1) Catalyst of breeding self-reliance
2) A facilitator of creation of wealth
3) An enabler for gaining global leadership
... (I missed a few here)

Space should become the bedrock on which the national systems for societal and strategic imperatives are builtup.

Expanding horizons:
1) Self reliance in satellites
2) Self reliance in space transportation
3) Interplanetary exploration (Chandrayaan has brought a new era in this.)
4) Low cost access to space
5) Human presence in space system

Space applications:
2009: 211 transponders in space, of which 195 are in use
2014: 500 transponders target
These are used in communication, DTH service, tele-medicine etc.

Ground water bore-well success rate has increased from 50% to 90% due to groundwater imaging use
Rs2-6 lakhs per fishing vessel are saved along with human effort and time! Fishermen can come home early with a greater catch!

Disaster management:
Remote sensing is used to identify the areas affected and Satellite based communication used to restore communication to the affected areas to help recovery efforts.

Satellite navigation program:
GAGAN is going to be used to augment GPS in the region, this project is being executed by Airport authority of India and ISRO as a joint project.
IRNSS is being developed for strategic purposes. 7 satellites will be launched.

Satellite systems:
Cartosat-2 has the agile system for satellite control, this system will also be used for the space shuttle program.
GSAT-4 has Ka band transponders
Studsat, a student satellite will be launched on the next PSLV. This is along with other student satellites like Jugnu, Anusat etc being developed by the students.

Earth observation and science systems:
Challenges exist in sensor development, detectors and processing of the data.
GSAT4 mission will have plasma thrusters for keeping on station.

Space transport:
GSLV MkIII can launch 10K ton in Leo, 4kton in GTO, will produce 640twt (?)

PSLV normal mode: 1600kg
PSLV core alone mode: 1100kg
PSLV XL mode: 1750kg (used for chandrayaan)

For the first time two launches are being prepared in parallel

GSAT-4 has already been mated with the vehicle, tentative date of launch April 15

PSLC-C15 launch target early may, will launch ALsat from Algeria, studsat and NLSat6.1&6.2(Canada) along with Cartosat2B (<0.8 meter resolution.)

C-16 will carry Resource sat and Youthsat (made by Univ. students of India and Russia), GSAT-8 and Hylas from Avanti,UK.

The target is now to look for 6-8 launches per year.

Passive model of Scramjet to study the aerodynamics of the structure has been tested recently.

Chandrayaan mission:
First time India attempted the following:
Lunar insertion
Complex spacecraft with 11 payloads
High accuracy, autonomous navigation system based on accelerometers and gyros with micro g precision for vehicle and spacecraft.
Multiple firing capability for liquid engine
Deep space mission 4 lakh kms in one attempt
Deep space network, payload operations and processing
Higher Electromagnetic radiation, thermal environment for spacecraft and payload
Clean separation from mother spacecraft of payload Lunar impact probe

Chandrayaan-2 mission:
Will consist of a lander and a rover
Lander will be Russian, spacecraft and rover will be Indian

Please note I have not been able to take good notes on this one, however most of the talk was on things that we know already, as told by K Prasad. This ET article does a good job of summarizing the talk, kudos to the reporter. italics=my comments

Varoon Shekhar · Post by **Varoon Shekhar** » 08 Apr 2010 18:10

"C-16 will carry Resource sat and Youthsat (made by Univ. students of India and Russia), GSAT-8 and Hylas from Avanti,UK."

Very good information you posted. Not to nitpick, but this can't be accurate right? This must be a reference to two or more different missions.

ISRO website has details of the GSLV Mark 2 mission:

http://isro.org/news/pdf/GSLV-D3.pdf

KrishG · Post by **KrishG** » 08 Apr 2010 19:36

K Mehta wrote:ISRO saga forward-Technological Dimension Dr K Radhakrishnan ......................

Thanks for the summary Mehtaji!

babbupandey · Post by **babbupandey** » 08 Apr 2010 20:37

http://www.deccanherald.com/content/625 ... enic.html?

But he asserted: "The (cryogenic) engine is designed by our own engineers, our own industry fabricated it, tested...". He added: "It's Indian. You should be proud of it".
ISRO officials recalled that the US exerted pressure on Russia not to provide cryogenic technology and India took a bold decision in 1992 to develop it indigenously.

Of the seven engines supplied by Russia earlier, ISRO has used five. Radhakrishnan said India developing this complex technology is a "befitting reply" to technology denial regimes.

Could it be that the other two (or one are used for reverse engineering? I think it is likely.

svinayak · Post by **svinayak** » 08 Apr 2010 21:47

babbupandey wrote:
Could it be that the other two (or one are used for reverse engineering? I think it is likely.

The others are used are used or emergency.

babbupandey · Post by **babbupandey** » 08 Apr 2010 23:19

Acharya wrote:
babbupandey wrote:
Could it be that the other two (or one are used for reverse engineering? I think it is likely.
The others are used are used or emergency.

I think the temptation to reverse engineer would be great, at least to get an idea. Indians have been reverse-engineering Russian weapons for a long time.

nachiket · Post by **nachiket** » 09 Apr 2010 02:14

babbupandey wrote: Indians have been reverse-engineering Russian weapons for a long time.

If only that had been so!

arun · Post by **arun** » 09 Apr 2010 13:24

Varoon Shekhar wrote: ........... ISRO website has details of the GSLV Mark 2 mission:

http://isro.org/news/pdf/GSLV-D3.pdf

The GSLV-D3 launch is certainly an important launch going by the number of firsts

.

On going through the ISRO link you posted the launch vehicle besides the cryogenic upper stage has a number of other firsts. These firsts include Composite Carbon Fibre-Reinforced Plastic Payload Fairing (PLF),Advanced Mission Computer (AMC) and Advanced Telemetry System (ATS) packages.

Likewise the GSAT 4 satellite payload will have a number of firsts:

1) Xenon based Electric Propulsion System to perform North South Station Keeping,
2) Integrated Bus Management Unit (BMU) which combines the functions of Telemetry, Telecommand, Sensor Electronics and Control Electronics;
3) 1553 Bus for Data Communication;
4) Miniaturised Dynamically Tuned Gyros;
5) 36 AH Lithium Ion Battery;
6) 70 V Bus for Ka band TWTAs.
7) First GAGAN Module.

K Mehta · Post by **K Mehta** » 09 Apr 2010 13:34

Varoon Shekhar wrote:"C-16 will carry Resource sat and Youthsat (made by Univ. students of India and Russia), GSAT-8 and Hylas from Avanti,UK."

Very good information you posted. Not to nitpick, but this can't be accurate right? This must be a reference to two or more different missions.

ISRO website has details of the GSLV Mark 2 mission:

http://isro.org/news/pdf/GSLV-D3.pdf

The link you have given is about GSLV.
C-16 is a PSLV mission. youthsat ~~i believe is most probably a nano sat.~~
edit: from ISRO site

YOUTHSAT
YOUTHSAT is a participatory scientific mission with payloads from both Russia and India. It would be carrying three scientific payloads one from Russia and two from India.

It is a micro satellite carrying scientific payloads with participation from universities at graduate, postgraduate and research scholar level and would participate from testing of the payloads in laboratory to the utilisation of the data from payloads. Participation of young scientists will inculcate interest in space related activities and provide opportunities for realisation of future scientific payloads at the university level. YOUTHSAT is scheduled to be launched as auxiliary satellite along with Indian remote sensing satellite during 2010 with an orbital altitude of 630 km at an inclination of 97.9º.

I havent paid much attention while writing notes in this lecture, so i might be wrong!
my notes go like this
C16-> resource sat and youthsat (univ students in India and Ru)
GSAT-8,5P Hylas->UK (oops again, error in the notes it should be5,8P )
GSAT-6-> multimedia services

Varoon Shekhar · Post by **Varoon Shekhar** » 10 Apr 2010 01:48

Another good article about the readiness; it's now on the launch pad, virtually ready to go!

GSLV-D3 ready for launch on April 15

a_kumar · Post by **a_kumar** » 10 Apr 2010 02:06

http://www.deccanherald.com/content/625 ... enic.html?

But he asserted: "The (cryogenic) engine is designed by our own engineers, our own industry fabricated it, tested...". He added: "It's Indian. You should be proud of it".

Radhakrishnan said India developing this complex technology is a "befitting reply" to technology denial regimes.

I wish they saved this for "after a successful launch"!

arun · Post by **arun** » 10 Apr 2010 09:14

A decent picture of the GSLV-D3 at the launch pad from the Hindu :

GSLV-D3 Picture

Vivek K · Post by **Vivek K** » 10 Apr 2010 09:32

a_kumar wrote:http://www.deccanherald.com/content/625 ... enic.html?
But he asserted: "The (cryogenic) engine is designed by our own engineers, our own industry fabricated it, tested...". He added: "It's Indian. You should be proud of it".

Radhakrishnan said India developing this complex technology is a "befitting reply" to technology denial regimes.
I wish they saved this for "after a successful launch"!

Second that Wish!!

VikB · Post by **VikB** » 10 Apr 2010 12:38

Finished reading "Wings of fire" by APJ Kalam yesterday. Awesome book. Many of things we take for granted today has come from the vision and hard work of a few people. I am perplexed that why our country does not celebrate the individual instead of thinking that some vague mass of people are doing what we believe they should be doing.

Time to remember Dr Brahm Prakash and Prof Vikram Sarabhai.

SSridhar · Post by **SSridhar** » 11 Apr 2010 05:01

First of the IRNSS satellites to be launched next year

Bade · Post by **Bade** » 12 Apr 2010 10:08

disha wrote:
arun wrote:^^^ it would be correct to assume that Tauvex will not be a part of the GSLV D3 payload.

PTI via Deccan Herald:

ISRO receives flak for delay in launching Israeli satellite
Too much Rona & Dhona (R&Dh) by the DDM reporter.

First of all GSLV D3 is a development vehicle and has not been commercialized as the name suggests. So there is no point in putting a "commercial" payload on a development flight. Second there are questions raised by ISRO itself on the need for TAUVEX being at geo-stationary orbit. Note that ISRO has more experience operating various satellites in various orbits. So if they have concerns, they have. Either the TAUVEX proj. mgmt. understands this and addresses it or complains about it. Complaining about it will not get them anywhere. They can do more Rona & Dhona, if TAUVEX needs to be in Geo orbit and when GSLV Cx has a slot it will take it there. If it needs to be in other orbit and if PSLV suffices it will be that way.

Tauvex has been in the can for almost a decade. It was to fly with the russians before isro came in to the picture. UV detectors have degrading sensitivity with time. Oxidation of the reflective coating in the optics make it more absorptive. Too bad for Tauvex. It could also have provided a learning experience for Indian scientists before the upcoming Astrosat launch.

Gagan · Post by **Gagan** » 12 Apr 2010 13:02

Is it me or this article on the BR front page has GAGAN and IRNSS confused:

Apr 15 launch to give India its GPS

SSridhar · Post by **SSridhar** » 12 Apr 2010 13:28

Gagan wrote:Is it me or this article on the BR front page has GAGAN and IRNSS confused:

Apr 15 launch to give India its GPS

I think that title is incomplete leading to confusion. India won't get its GPS-equivalent with GAGAN. That will happen when IRNSS satellites are placed in orbit. GAGAN uses GPS signals to provide a satellite based and augmented system for aircraft positioning for all phases of flight over Indian airspace.

merlin · Post by **merlin** » 12 Apr 2010 16:50

SSridhar wrote:
Gagan wrote:Is it me or this article on the BR front page has GAGAN and IRNSS confused:

Apr 15 launch to give India its GPS
I think that title is incomplete leading to confusion. India won't get its GPS-equivalent with GAGAN. That will happen when IRNSS satellites are placed in orbit. GAGAN uses GPS signals to provide a satellite based and augmented system for aircraft positioning for all phases of flight over Indian airspace.

More precisely GAGAN provides WAAS compatible correction signals that augment the GPS signal.

Kailash · Post by **Kailash** » 12 Apr 2010 16:51

Chandrayaan-II: PRL proposals under review

Varoon Shekhar · Post by **Varoon Shekhar** » 12 Apr 2010 18:41

"kumar wrote:
http://www.deccanherald.com/content/625 ... genic.html?
Quote:
But he asserted: "The (cryogenic) engine is designed by our own engineers, our own industry fabricated it, tested...". He added: "It's Indian. You should be proud of it".

Radhakrishnan said India developing this complex technology is a "befitting reply" to technology denial regimes.

I wish they saved this for "after a successful launch"!

Second that Wish!!"

Yes it is better to save such exaltation for after a successful launch. But one possibility is that they are extremely confident of a successful launch. There's an anecdote about the 2nd PSLV launch, after the first one failed, from an old issue of "Business India"(Nov/1994). Some scientists were so certain that it would succeed, that they gave their congratulations to the mission team scientists/engineers in advance, and left the launch area. Sure enough, it was big success.

Probably the same conditions don't apply here, but we can always hope

marimuthu · Post by **marimuthu** » 12 Apr 2010 20:52

GSLV D3 and GSAT4 Images

Sridhar · Post by **Sridhar** » 13 Apr 2010 06:00

Nice pictures there. Just a question that I have been curious about - perhaps somebody here knows. Is there a particular reason for the cryogenic stage alone to be painted black, whereas other stages all have white paint? I have seen that with the Russian cryogenic stage as well.

ramana · Post by **ramana** » 13 Apr 2010 06:14

Sridhar, Maybe for radiative heat transfer purposes? Keep the cryogenic stage from freezing over?

disha · Post by **disha** » 13 Apr 2010 07:37

Sridhar wrote:Nice pictures there. Just a question that I have been curious about - perhaps somebody here knows. Is there a particular reason for the cryogenic stage alone to be painted black, whereas other stages all have white paint? I have seen that with the Russian cryogenic stage as well.

There is lot one can learn from the pictures itself! For the above question, my theory - to avoid moisture condensation or ability to see "moisture" when it freezes on a black background.

Added later: They could be ablator coatings for the third stage.

Bade · Post by **Bade** » 13 Apr 2010 07:59

For the best thermal characterization and stability. Black body spectrum for all wavelengths ( infra-red should be the dominant case here) is exactly given by the planck's law. Keeps the thermal equilibrium inside and the immediate outside very stable for the enclosure by making it approximate a perfect black body.

SSridhar · Post by **SSridhar** » 13 Apr 2010 11:50

Sridhar wrote:Is there a particular reason for the cryogenic stage alone to be painted black, whereas other stages all have white paint? I have seen that with the Russian cryogenic stage as well.

In a solid propellant motor, whether case bonded or not, there are two layers internally, one of an insulator and the other of a liner, between the propellant and the case. The insulator limits heat transfer to the case while the liner bonds the propellant and the case. They both do not contain any oxidizing material so that they may not burn by themselves. An outer coat of paint is usually not required except for aesthetic reasons.

OTOH, the effort in a cryogenic stage is to prevent heat generated by the friction with the dense atmosphere through the ascent to cause the liquid Hydrogen & Oxygen from vapourizing. Among other measures, a high-temperature paint coat is applied which is generally non-pyrolizing with low-thermal conductivity. Black colour is better.

Sridhar · Post by **Sridhar** » 13 Apr 2010 15:07

Thanks! This is very informative.

Katare · Post by **Katare** » 14 Apr 2010 05:14

ISRO's Radhakrishnan reveals on NDTV that govt will give its approval for manned space mission within next two months. The cost would be Rs12400Corer and it'll take 7 years from the approval.

Carl_T · Post by **Carl_T** » 14 Apr 2010 05:41

Damn, I thought the manned flight was going to be in 2015. But nothing wrong in waiting as long as we get there!

SSridhar · Post by **SSridhar** » 14 Apr 2010 15:43

Countdown begins at SDSC

The 29-hour countdown for the lift-off of India’s Geo-synchronous Satellite Launch Vehicle (GSLV-D3) is proceeding satisfactorily for the launch to take place from Sriharikota on April 15 at 4.27 p.m. The countdown began at 11.27 a.m. on Wednesday, April 14.

Filling of the second stage and the four strap-on booster motors with liquid propellants will be completed during the 29-hour countdown. “The filling of the cryogenic engine with liquid hydrogen and liquid oxygen will continue till almost the end of the countdown. This is to prevent loss of cryogenic fluids due to evaporation,” said Mr. Satish. Certain mandatory checks of the vehicle and charging of the batteries in both the rocket and the satellite would be done during this countdown.

SSridhar · Post by **SSridhar** » 14 Apr 2010 15:49

GSLV-D3 & GSAT-4 Brochure

Narad · Post by **Narad** » 14 Apr 2010 16:13

Any confirmation whether the launch would be covered on DD.

rakall · Post by **rakall** » 14 Apr 2010 17:31

Narad wrote:Any confirmation whether the launch would be covered on DD.

It is generally covered on DD.
Only Tecsar launch was an exception.

Varoon Shekhar · Post by **Varoon Shekhar** » 14 Apr 2010 18:27

http://www.vigyanprasar.gov.in/comcom/develop16.htm

"Technology has been developed for nickel electroforming of the thrust chamber of the cryogenic rocket engine for ISRO .."

Is it sensible to assume that this process/technology has been applied in the ISRO made cryogenic engine?

Article is from the 90's.