Indian Space Programme Discussion

Austin · Post by **Austin** » 18 Aug 2015 17:56

India's Mars Orbiter captures stunning photo of solar system’s largest canyon

member_23694 · Post by **member_23694** » 19 Aug 2015 14:41

ISRO ‏@isro
GSLV-D6 / GSAT-6 Launch on Aug 27, 2015 at 16:52 Hrs IST

SaiK · Post by **SaiK** » 19 Aug 2015 14:53

they have not listed the D6 here
http://www.isro.gov.in/category-launche ... gslv-mk-ii

member_28108 · Post by **member_28108** » 19 Aug 2015 22:14

SaiK wrote:they have not listed the D6 here
http://www.isro.gov.in/category-launche ... gslv-mk-ii

Those are completed launches.

Neela · Post by **Neela** » 20 Aug 2015 17:46

GSLV-D6 GSAT-6 Mission PDF

2nd(?) run of CE7.5

Varoon Shekhar · Post by **Varoon Shekhar** » 20 Aug 2015 19:02

^
With the satellite weighing in this time at 2117 kg, would they have made some modifications to any of the stages, or is the weight/mass well within the margins of the vehicle's capability. The last flight of the GSLV Mark 2 carried a 1982 kg satellite, so it's an addition of 135 kg.

SSSalvi · Post by **SSSalvi** » 20 Aug 2015 22:24

40 years back, starting 1st August 1975, For the first time in the world an experiment to transmit signals directly from the satellite to a community TV was conducted using a US satellite ATS-6 and Direct Reception sets ( DRS ) in over 2000 TV sets in India.

Called SITE ( Satellite Instructional Television Experiment ), this experiment provided data base for studies in Community TV.

One of the managers of this experiment compiles the facts here.

The B/W picture shows one of the first large antennas in India, a starting point of career in satcom for many youngsters then ( including the name on the left ).

Rahul M · Post by **Rahul M** » 20 Aug 2015 22:50

Sir ji, please write an article or two on your experiences. we would be glad to carry it on BR's SRR mag.

member_23694 · Post by **member_23694** » 20 Aug 2015 23:03

Varoon Shekhar wrote:^
With the satellite weighing in this time at 2117 kg, would they have made some modifications to any of the stages, or is the weight/mass well within the margins of the vehicle's capability. The last flight of the GSLV Mark 2 carried a 1982 kg satellite, so it's an addition of 135 kg.

http://www.frontline.in/cover-story/wil ... 590227.ece

The April 15, 2010 flight, which was the first to use India’s own cryogenic stage, was to put a GSAT that weighed 2,220 kg into orbit. But GSLV-D5 used a 1,983-kg GSAT-14. So, the payload was lighter by 240 kg in the successful GSLV-D5 mission. Does this detract from its success?

After we faced the failure of GSLV-D3 and lost the GSAT-4 satellite, we thought it was prudent to play it safe and keep the primary mission objective of GSLV-D5 as proving the indigenous cryo stage in flight with the deployment of a satellite as an additional bonus. As such, we planned a lighter GSAT-14 with fewer transponders to keep the cost low. Also, the urge to make the CUS more robust in this second attempt, especially after the GSLV-F06 failure, attributed to the deflection and breaking of the shroud in the cryo stage, did indeed increase the inert weight of the CUS in GSLV-D5. All these factors made us attempt GSLV-D5 with GSAT-14 weighing less than GSAT-4 of GSLV-D3. However, this in no way brings down the significance of proving successfully the indigenous cryo stage. The restoration of payload to two-tonne-plus will happen in the very next flight through the optimisation of inert mass and a realistic pruning of margins.

I can confidently say that once we have a working cryo stage and the GSLV, enhancing its performance or payload incrementally is bound to happen in subsequent flights, as demonstrated in the case of the PSLV.

Hiten · Post by **Hiten** » 21 Aug 2015 15:22

.
After MOM, ISRO Will Send PAPA Into Space

The Plasma Analyser Package for Aditya [PAPA] payload on-board the Aditya-L1 satellite would be used for, "studying the composition of solar wind and its energy distribution continuously throughout the mission’s life time". The Indian Space Research Organisation [ISRO] is expected to launch its maiden mission to the Sun in 2019, 6 years after it launched the Mars Orbiter Mission [MOM], its maiden trip to the red plant.

via http://www.aame.in/2015/08/after-mom-is ... space.html

Hiten · Post by **Hiten** » 21 Aug 2015 15:30

.
ASTROSAT

Chandrayaan-2

Chandrayaan-1

far side of Mars' Moon Deimos photographed by MOM

more details:
http://www.planetary.org/blogs/emily-la ... mages.html

chetak · Post by **chetak** » 21 Aug 2015 23:35

Engadget ‏@engadget Aug 17
Indian probe captures 3D image of vast Mars canyon http://www.engadget.com/2015/08/17/mars ... on-images/ …

91 retweets 60 favorites

member_28108 · Post by **member_28108** » 23 Aug 2015 17:54

http://zeenews.india.com/news/science/f ... 50884.html

FIPIC summit: PM Modi announces plan to open space station in Pacific Islands nation
Last Updated: Saturday, August 22, 2015 - 00:21
1 Comment

Jaipur: Pushing for deeper cooperation with 14 nations of strategically-located Pacific region, Prime Minister Narendra Modi today announced a number of initiatives, including setting up of a space station in any of the countries and developing capacities in disaster management.

Addressing the Summit of Forum for India-Pacific Island Conference (FIPIC) here, he said cooperation could immediately begin with research collaboration and capacity building with institutions in India.

He offered to create capacity in these Island states in dealing with natural disasters, including through human resource development and application of space technology for early warning system and incident response.

Talking about Indian Navy's support and capacity building efforts in island states in Indian Ocean, he pitched for goodwill visits by Indian Navy to Pacific Islands saying the ships could also provide support to the islands in areas like healthcare through medical camps.

Modi, while highlighting Fiji's support for India's Mars Mission, talked about establishing a Space Technology Applications Centre in any one of the Pacific Island countries, for the entire region.

He told the assembly of heads of states and governments and other delegates that efforts would be made to enhance support for training in space applications, including through customised courses.

Modi, who also had bilateral meetings with a number of leaders present here, hoped for continuing support from the Pacific Islands for Telemetry, Tracking and Command for the country's missions in the future.

He also proposed to hold an International Conference on Ocean economy and Pacific Island Countries in New Delhi next year for officials and experts of all the 14 Pacific Island countries.

In the area of human resource development, he announced that Fiji will get 110 slots for the Indian Technical and Economic Cooperation and the number of slots for remaining 13 countries will be doubled from 119 to 238.

Modi also announced two scholarships for college education in India to each of the 13 countries that do not receive them yet, while continuing with the 33 scholarships presently offered to Fiji.

We will expand our training courses for Pacific Island diplomats and a two-week business management course at the Indian Institute of Management in Bengaluru, he said.

In a move aimed at saving kerosene worth about a million US dollars and providing livelihood to women, Modi said that India would train 70 women solar engineers from the islands and provide solar electrification to 2,800 houses - 200 houses in each Pacific Island Country.

Underlining that climate change is a pressing concern for all, the Prime Minister said, "We must equally seek a global commitment to support adaptation to the growing impact of climate change on our lives and economy," an apparent message to the developed world.

"Combating it is India s national priority. We made this choice with the natural instinct of our heritage and culture. But we also do this in our enlightened self-interest and with a commitment to the future of our planet," he said.

The Prime Minister said India will work with these island nations and others for a comprehensive, balanced and fair outcome at COP-21 (Conference of Parties) in Paris in November this year.

India and the Pacific island nations should work together for a separate goal on climate change in the Sustainable Development Goals, and in a manner that addresses the interests of developing countries, Modi said.

Pushing for reform of the UN, the Prime Minister asserted that the global body must keep pace with the changing time as the world today is a different place seven decades after it was created.

He sought the support of Pacific island nations to India s bid for permanent seat in the expanded UN Security Council.

"Your voice of support for India's permanent membership of the Security Council will give the United Nations the global character and balance that mirrors our age, he said, adding the UN is at a historic milestone of its 70th anniversary.

"I have written to all member states on charting the course for the United Nations for the years ahead. Seven decades after the UN was created, the world is a different place. We have four times as many nations. We have new challenges like climate change. We have new frontiers like Space and Ocean. We live in a globalised world with a transformed economy in a digital age," he said.

The United Nations must keep pace with the changing world, Modi said.

Pushing for reforms in the UN Security Council to ensure its relevance and effectiveness in the 21st century, Modi sought support of the island nations for reforming the Security Council.

India, he said, will support the realisation of vision of the island countries for Pacific Regionalism.

He said the reform of the UN Security Council is in global interest and vital for more inclusive and equitable world.

The draft presented by the President of the General Assembly as the negotiating text should be adopted quickly and the negotiations concluded during the 70th session of the General Assembly (next month), Modi said.

PTI

First Published: Friday, August 21, 2015 - 22:48

SSSalvi · Post by **SSSalvi** » 23 Aug 2015 22:31

GSAT-6 / INSAT-4E satellite is planned for launch on 27th Aug2015 at 1652 hours aboard GSLV D6 ( 5th Demo ) flight using 3rd Indegenous Cryo engine in 2nd stage.
GSAT-6 is a multi-media mobile applications satellite system at a total estimated cost of Rs. 269 crores (Rs. 102 crores in FE )
Satellite Digital Multimedia Broadcasting (S-DMB) service, via mobile phones and mobile video/audio receivers for vehicles.

This satellite will also provide a platform for developing techniques and technologies which will be useful in future satellite based mobile communication applications such as demonstration of large unfurlable antenna in spacecraft, handheld ground terminals and network management techniques.

It will be positioned at 83 deg East longitude.

INSAT-4 series is planned to have seven satellites, INSAT-4A through INSAT-4G with INSAT-4D as a spare.

The spacecraft has 440 Newton thrust liquid apogee motor for maneuver and 2 deployable solar arrays generating 3100 W power.
It has dimensions ( in launch configuration ) of 2.1M x 2.5M x 4.1M
Mission Lifetime 9 years
Mass 2117 kg ( 1132 kg is propellants weight + dry mass of the satellite, 985 kg )

One of the advanced features of GSAT-6 satellite is its S-Band unfurlable Antenna of 6 m diameter, the largest satellite antenna made by ISRO. The greatest challenge was to accommodate it in 2.5 metre dia of Satellite housing by folding the antenna like an umbrella. Next image shows the antenna in two modes and later image shows the antenna mounted on spacecraft.

The folded umbrella would be unfurled after the satellite is in positioned in the orbit slot using Pyro-initiated release mechanism. The antenna has a perimeter truss consisting of composite tubes to support the front and rear webs with fibre reinforcement. ( attempted for the first time. )

This antenna is utilised for five spot beams over the Indian main land: It will have,
- 5 C × S transponders ( each of 9 MHz bandwidth ) and
- 5 S × C transponders ( each of 2.7 MHz bandwidth )

The spot beams exploit the frequency reuse scheme to increase frequency spectrum utilisation efficiency.

For the first time a 70V power bus is used to cater to the high power requirement of transponders.

After its injection into GTO by orbit raising manoeuvres by repeatedly firing the Liquid Apogee Motor (LAM) on-board the satellite, will finally place it in the circular Geostationary Orbit at 83 deg East longitude.

( Info compiled from several sources )

member_28108 · Post by **member_28108** » 24 Aug 2015 06:35

S-Band unfurlable Antenna of 6 m diameter

Mort Walker · Post by **Mort Walker** » 24 Aug 2015 09:26

I can't tell from looking at the pictures, but what I gather is that the spacecraft itself is the focal point with 3 locations on it?

Let me get this right, 5 transponders with 9 MHz each and 5 transponders with 2.7 MHz each. A total bandwidth of 58.5 MHz?

A 6m antenna that is roughly parabolic at C-Band means a gain of nearly 50 dB or 100,000 times and beam resolution of nearly 0.5 degrees. Uh...this doesn't look like a multimedia broadcasting service for saas-bahu TV serials, rather it looks like a very sensitive (low noise) communications surveillance eavesdropping system.

SSSalvi · Post by **SSSalvi** » 24 Aug 2015 15:26

^^^
Nowhere it is mentioned that this satellite is for saasbahu serials.
Yes from image we can deduce that there are 3 horns and basic calculations give a beamwidth of .6 .. but that is for 3 db .. with a handheld equipment you have to have at least 20 db margin so coverage zone will be at least 3000 kms and with 3 horns that will cover entire bharat saasbahus or men in khaki.

Qoting from one of the news channels :

The GSAT-6/INSAT-4E satellite was conceived in 2005 to provide entertainment and information services to consumers and vehicles through digital multimedia consoles and multimedia mobile phones. The satellite was earmarked for use Devas Multimedia Pvt. Ltd. in a Rs 1,000 crore deal between Antrix Corporation and Devas Multimedia.

Later, the government assigned the satellite for military use, prompting Devas to take Antrix to court.

So there is no hush hush .. yes, earlier ( devas ) it was for a commercial setup for handheld for common man.

Varoon Shekhar · Post by **Varoon Shekhar** » 24 Aug 2015 17:07

SSSalvi, what about GSAT-14( launched by GSLV D-5), is that also likely being used for strategic, surveillance purposes? Or purely testing reasons? And when a satellite is used for "testing", how long is it used for that purpose? By now, they would have certified the success of certain payloads, wouldn't they, like the solar power system on board. So they can transfer it to Doordarshan or any other TV network?

India, we are told, is currently facing a shortage of indigenous transponder capacity, leading to foreign players grabbing a large chunk of the telesat market.

So how can it be justified to have 2 out of the last 3 geosynchronous satellites for non-commercial reasons? Or do they have enough satellites for commercial telecom and I&B lined up as well?

SSSalvi · Post by **SSSalvi** » 24 Aug 2015 21:41

^^^
Generally testing is over in less than a month.

A very good compilation of current status of various transponders is available at lyngsat.com

We can find GSAT14 at 74E ( Last entry at bottom right in the table ) at this link : http://www.lyngsat.com/tracker/asia.html

For some curious reason GSAT7 and GSAT14 don't show freq usage chart.

e.g you can see freq usage of INSAT3C and 4CR ( co-located at 74E ) by clicking on their names and when the next page come click on Freq Chart.

TV channels can be placed on any foreign satellite ( of course at some cost ) but for strategic usage that freedome is not there,,
Let someone have a liberty to decide the priority. We, commoners, don't have idea of every fact.

member_28108 · Post by **member_28108** » 24 Aug 2015 21:44

Remember that these are investigational satellites to test various things including the GSLV itself.(That is why it is given the D designation)

Gagan · Post by **Gagan** » 24 Aug 2015 22:44

Saar
What types of comms can this intercept?

putnanja · Post by **putnanja** » 25 Aug 2015 06:00

From ISRO Website on GSAT 6 :

GSAT-6 Satellite provides communication through five spot beams in S-band and a national beam in C-band for strategic users. The cuboid shaped GSAT-6 has a lift-off mass of 2117 kg. Of this, propellants weigh 1132 kg and the dry mass of the satellite is 985 kg.

Mort Walker · Post by **Mort Walker** » 25 Aug 2015 07:21

putnanja,

Thanks for the ISRO link.

Gagan wrote:What types of comms can this intercept?

Satellite comms are mostly all in the C-Band between 5.5-6 GHz. On the receive side, if the receiver is tuned for a 1 MHz bandwidth, the theoretical noise floor is -114 dBm or 4 femto-watts. Given antenna gain, resolution, very linear 16-bit A/Ds in parallel, and some signal processing methods - my guess is that they can resolve signals around -103 dBm or 50 femto-watts. Just to come up with this idea, build and prepare for launch is truly amazing and is a huge accomplishment for ISRO.

Should the GSAT 6 be a successful launch and deployment, and if I were the US, Russia or China, then there is full reason to be concerned that India may be able intercept my communications.

SSSalvi · Post by **SSSalvi** » 25 Aug 2015 09:10

^^^
Dunno abt beam coverage.
Still - yes - you can be worried in Russia or China
USofA.. how?

member_28108 · Post by **member_28108** » 25 Aug 2015 19:31

http://www.isro.gov.in/space-applicatio ... ar-of-site

Mort Walker · Post by **Mort Walker** » 25 Aug 2015 19:51

SSSalvi wrote:^^^
Dunno abt beam coverage.
Still - yes - you can be worried in Russia or China
USofA.. how?

Beam coverage within the 3 dB spot would depend on where you could point your antenna. Any organization that has an orbital C-band communications satellite would be fair game for surveillance. Friend or foe.

Varoon Shekhar · Post by **Varoon Shekhar** » 25 Aug 2015 21:08

How many more launches of the GSLV before we can realistically expect a commercial launch i.e of another country's geosynchronous satellite? We do know that the PSLV started launching foreign satellites after 3 successful missions, D-2, D-3 and C-1

PSLV C-2 carried Kitsat and Tubsat from S. Korea and Germany respectively.

Of course, the country in question would need to have a satellite under 2200kg, that goes into that GSO orbit. What are the market segments for this type of satellite? Perhaps countries like Indonesia, Brazil, Singapore with experimental GSO sats?

member_28108 · Post by **member_28108** » 25 Aug 2015 21:27

The GSLV Mk2 will probably have to go for 3 consecutive flights before converting it to a regular launch vehicle but I think by that time the GSLV Mark 3 will be the vehicle followed by the ULMV that will be used for commerical launches for non Indian payloads. The Mark 2 was really for mastering cryogenic technology. Once we have done that it makes sense to use the Mark 3 which can launch 4 tone satellite class.

Varoon Shekhar · Post by **Varoon Shekhar** » 25 Aug 2015 21:41

That makes sense, thanks. I just hope they make good use( preferably civilian, but even otherwise) of the satellites they do send up with the current GSLV Mark 2, and that they are not just for pure testing purposes. Satellites are not easy to build, nor inexpensive.

member_28108 · Post by **member_28108** » 25 Aug 2015 21:48

Have you seen the configuration of GSAT^ ? It will be put to good use. I don't think anyone is going to spend 250 Crores and send a dud ! One thing though is that in an experimental satellite they will keep less number of transponders as these are experimental flights.

thammu · Post by **thammu** » 26 Aug 2015 12:21

From ISRO FB page

GSLV-D6 / GSAT-6 Update:
The 29 hr countdown activity of GSLV-D6/GSAT-6 Mission has commenced today, Wednesday, Aug 26, 2015 at 11:52 hr IST Launch is scheduled at 16:52 hr IST on Aug 27, 2015

SSSalvi · Post by **SSSalvi** » 26 Aug 2015 14:45

Mort Walker wrote:
SSSalvi wrote:^^^
Dunno abt beam coverage.
Still - yes - you can be worried in Russia or China
USofA.. how?
Beam coverage within the 3 dB spot would depend on where you could point your antenna. Any organization that has an orbital C-band communications satellite would be fair game for surveillance. Friend or foe.

No satellite over India can cover US .. hence my comment.

Anyway this topic is closed from my side.

shravanp · Post by **shravanp** » 26 Aug 2015 18:20

More images :http://www.isro.gov.in/launcher/gslv-d6

Varoon Shekhar · Post by **Varoon Shekhar** » 26 Aug 2015 18:25

Beautiful pics, thanks! What is that large, concrete looking structure to the right of the launch pad, at the top of the page?

prashanth · Post by **prashanth** » 26 Aug 2015 18:56

I was told it is a water tank. Water from this tank is used to cool the pad during launch. IIRC, the tank empties in a few tens of seconds.

Vipul · Post by **Vipul** » 26 Aug 2015 21:18

Countdown begins for launch of Indian military satellite.

A government-owned communications satellite heading for geostationary orbit 22,300 miles above Earth is set for launch Thursday to on a nine-year mission to to support the Indian military.

The 4,667-pound GSAT 6 spacecraft will lift off aboard India’s Geosynchronous Satellite Launch Vehicle at 1122 GMT (7:22 a.m. EDT) Thursday from the Satish Dhawan Space Center, a spaceport situated about 50 miles north of Chennai on India’s east coast.

Shrouded inside the GSLV’s metallic nose fairing, the satellite is India’s 25th geostationary communications satellite and has a mission to serve “strategic users,” according to the Indian Space Research Organization. Indian news reports said the prime customer for the new signal relay craft is the Indian military.

ISRO officials said the 29-hour countdown began Wednesday, and launch crews planned to fill the rocket’s four liquid-fueled boosters and second stage with storable hydrazine and nitrogen tetroxide propellants later in the day. Fueling of the GSLV’s third stage with cryogenic liquid hydrogen and liquid oxygen will come in the final hours of the countdown.

The first stage’s solid propellant load was packed inside the motor when it was assembled.

Launch is scheduled for 4:52 p.m. local time Thursday at the Indian launch base, and 161-foot-tall GSLV will fire away on the power of four hydrazine-burning strap-on Vikas booster engines and a solid-fueled core motor. At peak power, the first stage and the boosters will generate more than 1.7 million pounds of thrust.

The four liquid-fueled boosters will ignite at T-minus 4.8 seconds and ramp up to full thrust before the solid first stage fires when the countdown clock reaches zero.

The core motor will consume its propellant load by T+plus 1 minute, 46 seconds, followed by shutdown of the four Vikas booster engines at T+plus 2 minutes, 29 seconds. A single second stage Vikas powerplant will take over and burn until just shy of the mission’s five-minute point, during which time the GSLV’s payload fairing will release once the rocket is out of the dense lower atmosphere — a milestone projected at T+plus 3 minutes, 50 seconds.

A cryogenic upper stage engine will ignite at T+plus 4 minutes, 54 seconds, for a nearly 12-minute firing to propel the GSAT 6 satellite into an oval-shaped geostationary transfer orbit. Spacecraft separation is schedule for T+plus 17 minutes, 4 seconds, according to ISRO.

India's GSAT 6 communications satellite is pictured before encapsulation inside the GSLV's payload fairing. Credit: ISRO
India’s GSAT 6 communications satellite is pictured before encapsulation inside the GSLV’s payload fairing. Credit: ISRO
The launch is targeting an orbit with a high point of 22,353 miles (35,975 kilometers), a low point of 105 miles (170 kilometers) and an inclination of 19.95 degrees.

Thursday’s launch marks the third time the Indian-built cryogenic engine, which burns a super-cold mixture of liquid hydrogen and liquid oxygen, has flown on the GSLV. Earlier GSLV flights, dating back to the rocket’s maiden mission in 2001, employed a Russian-made cryogenic third stage.

The all-Indian version of the GSLV, called the GSLV Mk.2, failed on its first launch in April 2010 due to a failure in the upper stage engine’s liquid hydrogen turbopump. The second test launch of the GSLV Mk.2 in January 2014 was successful.

The launch of GSAT 6 is the ninth flight of the GSLV in both its all-Indian and part-Russian configurations. ISRO considers four of the eight launches to date as successful.

Thursday’s launch, designated GSLV-D6 by ISRO, is India’s third space mission of the year after two flawless flights of the smaller Polar Satellite Launch Vehicle.

GSAT 6 will fire its on-board propulsion system to circularize its orbit 22,300 miles above the equator, where it will park itself at 83 degrees east longitude and unfurl a nearly 20-foot (6-meter) S-band antenna, the largest reflector of its kind ever flown on an Indian communications satellite.

The spacecraft carries S-band and C-band communications payloads with five spot beams and one nationwide beam.

member_28108 · Post by **member_28108** » 26 Aug 2015 21:59

ISRO ‏@isro 2h2 hours ago
GSLV-D6 / GSAT-6 Update: Propellant filling operation of L40 Strap On Stages is under progress.

ISRO ‏@isro 5h5 hours ago
GSLV-D6 / GSAT-6 Update:Second Stage (GS2) UH25 filling completed at 17:46hr IST
92 retweets 105 favorites

GSLV-D6 / GSAT-6 Update: Second Stage (GS2) UH25 filling under progress

ISRO ‏@isro 8h8 hours ago
GSLV-D6 / GSAT-6 Update: Second Stage (GS2) N2O4 filling completed at 14:00hr IST

ISRO ‏@isro 10h10 hours ago
GSLV-D6 / GSAT-6 Update: Second Stage (GS2) N2O4 filling under progress

ISRO ‏@isro 11h11 hours ago
GSLV-D6 / GSAT-6 Update: The 29 hr countdown activity of GSLV-D6/GSAT-6 Mission has commenced today, Wednesday, Aug 26, 2015 at 11:52 hr IST

Tweets from @ISRO regarding countdown.

member_28108 · Post by **member_28108** » 26 Aug 2015 22:00

Picklu · Post by **Picklu** » 26 Aug 2015 22:46

The cryo stage looks like without hard casing.

sohamn · Post by **sohamn** » 26 Aug 2015 23:13

Picklu wrote:The cryo stage looks like without hard casing.

It surely has a hard casing, what you see if a thermal blanket to keep the LO2 and LH2 below boiling point. This will be removed before launch.