Indian Space Program Discussion

arun · Post by **arun** » 30 Sep 2010 13:53

Jeffrey Carr in a column written for Forbes Magazine and posted on their blog site speculates that the India’s INSAT 4 B Satellite may have been the real target of the attack by the Stuxnet worm initiated by the Peoples Republic of China :

Did The Stuxnet Worm Kill India’s INSAT-4B Satellite?

Posted by JEFFREY CARR

On July 7, 2010, a power glitch in the solar panels of India’s INSAT-4B satellite resulted in 12 of its 24 transponders shutting down. .......................

Once it became apparent that INSAT-4B was effectively dead, SunDirect ordered its servicemen to redirect customer satellite dishes to point to ASIASAT-5, a Chinese satellite owned and operated by Asia Satellite Telecommunications Co., Ltd (AsiaSat). AsiaSat’s two primary shareholders are General Electric and China International Trust and Investment Co. (CITIC), a state-owned company. China and India are competing with each other to see who will be the first to land another astronaut on the Moon. China has announced a date of 2025 while India is claiming 2020.

What does this have to do with the Stuxnet worm that’s infected thousands of systems, mostly in India and Iran? India’s Space Research Organization is a Siemens customer. According to the resumes of two former engineers who worked at the ISRO’s Liquid Propulsion Systems Centre, the Siemens software in use is Siemens S7-400 PLC and SIMATIC WinCC, both of which will activate the Stuxnet worm.

I uncovered this information as part of my background research for a paper that I’m presenting at the Black Hat Abu Dhabi conference in November. ......................

Forbes Blog

Shankar · Post by **Shankar** » 30 Sep 2010 20:27

ISRO today is quite busy in fact -fund constraint is no longer there - with semi cryogenic engine entering project stage -third launch pad and mk3 c-25 closing on test stage some delays are inevitable - GSLV launch was postponed as a matter of abundant caution but should fly before year is over - fault analysis is nearly over for mk2

Varoon Shekhar · Post by **Varoon Shekhar** » 30 Sep 2010 20:41

"GSLV launch was postponed as a matter of abundant caution but should fly before year is over - fault analysis is nearly over for mk2"

Whoa, are you referring to the GSLV with the Indian made cryogenic engine, or the GSLV with one of the remaining Russian engines? If the former, that is, like, really awesome man!

merlin · Post by **merlin** » 30 Sep 2010 21:03

Varoon Shekhar wrote:"GSLV launch was postponed as a matter of abundant caution but should fly before year is over - fault analysis is nearly over for mk2"

Whoa, are you referring to the GSLV with the Indian made cryogenic engine, or the GSLV with one of the remaining Russian engines? If the former, that is, like, really awesome man!

No, that would be GSLV with Russian engine. The Mk2 will be next year.

Shankar · Post by **Shankar** » 30 Sep 2010 22:38

yes with Russian cryo acceleration block-the Indian cryogenic engine will under go some modification before next flight

ramdas · Post by **ramdas** » 30 Sep 2010 23:21

Shankarji,

What does project stage mean ? Each year until now, funds on Semi-Cryo have hardly been spent...this may take a long time, it looks

Shankar · Post by **Shankar** » 01 Oct 2010 09:46

dont call me Ji boss - plain shankar sounds so much better

project stage means the basic specification of some first level of systems required for ground testing of the engines is over and procurement will start anytime (actual spending of money).The semi cryo that is lox kerosene engine basic design is available - separate system groups in place and consultants appointed

It is a big engine 200 T and uses liquid oxygen kerosene at very high pressure whcih calls for setting up everything up from scratch storage tanks piping test stands with all associated valves and instruments

for example a single heat exchanger cryogenic type for semi cryo engine testing will be more than 10 times the size used for GSLV mk 3
- donot even know how to configure it its so so huge and then make it -

some chaiwal said this onleee not me

Willy · Post by **Willy** » 01 Oct 2010 10:10

Varoon Shekhar wrote:"GSLV launch was postponed as a matter of abundant caution but should fly before year is over - fault analysis is nearly over for mk2"

Whoa, are you referring to the GSLV with the Indian made cryogenic engine, or the GSLV with one of the remaining Russian engines? If the former, that is, like, really awesome man!

How many of the Russian cryo engines are left? 3?

Shankar · Post by **Shankar** » 01 Oct 2010 11:47

we got as per press reports 7 engines so that means your numbers are correct
a pair may be kept in reserve always
Indian cryo engine is also ready -the small glitch which caused the engine to shut down immediately after ignitiong have been identified and taken care of
Even the bigger C25 engine is in advanced stage of fabrication and engine testing followed by thrust chamber testing and finally stage integration and testing die to be completed by next year .Once C25 is operational we may not need the C-12 any more

The feed back from development of C-12 will and is becoming a good source of data for fine tuning C-25

Shankar · Post by **Shankar** » 01 Oct 2010 15:55

ISRO TODAY

SEMI CRYO ENGINE
Thrust 200 tons
lox/kerosene

The basic design is complete.Procurement of materiel is in progress . Engine test facility under design. Cold test facility nearing completion.Storage facility for propellants ,design is nearly complete. Procurement action to start anytime

Thrust chamber pressure is 200 bar plus ,turbo pump outlet pressure is 400 bar , lox flow rate will be the order of 300 kg/sec and kerosene around 250/kg/sec

The propellant feed line to engine in the order of 150-200 mm suitable for 400 bar working pressure

the rocket will have semi cryo in fisrt stage followed by one C-25 full cryogenic engine with two nos S-200 solid boosters same as GSLV MK3
S-200 already qualified also L110 cluster already qualified .One for test for L110 under planning in cluster form

payload -6-8 ton s to geo synchronous orbit depending on vehicle configuration

next launch is PSLV with Resourcesat followed by GSLV MK1 with GSAT 5

Manned mission is approved . Another 4-5 years to flight as per schedule .

Chandrayan 2 is set to fly next year with Russian lunar rover on upgraded PSLV

R&D activities like nuclear propulsion and ion propulsion are progressing well - for inter planetary mission of future .Some ion propulsion components were qualified and put on GSLV MK 2 which failed and most likely will be put on next GSLV mk1 for GSAT 5 propulsion

Willy · Post by **Willy** » 01 Oct 2010 16:55

Shankar wrote:ISRO TODAY

SEMI CRYO ENGINE
Thrust 200 tons
lox/kerosene

The basic design is complete.Procurement of materiel is in progress . Engine test facility under design. Cold test facility nearing completion.Storage facility for propellants ,design is nearly complete. Procurement action to start anytime

Thrust chamber pressure is 200 bar plus ,turbo pump outlet pressure is 400 bar , lox flow rate will be the order of 300 kg/sec and kerosene around 250/kg/sec

The propellant feed line to engine in the order of 150-200 mm suitable for 400 bar working pressure

the rocket will have semi cryo in fisrt stage followed by one C-25 full cryogenic engine with two nos S-200 solid boosters same as GSLV MK3
S-200 already qualified also L110 cluster already qualified .One for test for L110 under planning in cluster form

payload -6-8 ton s to geo synchronous orbit depending on vehicle configuration

next launch is PSLV with Resourcesat followed by GSLV MK1 with GSAT 5

Manned mission is approved . Another 4-5 years to flight as per schedule .

Chandrayan 2 is set to fly next year with Russian lunar rover on upgraded PSLV

R&D activities like nuclear propulsion and ion propulsion are progressing well - for inter planetary mission of future .Some ion propulsion components were qualified and put on GSLV MK 2 which failed and most likely will be put on next GSLV mk1 for GSAT 5 propulsion

What will the new rocket to be powered by the new Semi-Cryo engine be called? The GSLV-MKIV ?

Tanaji · Post by **Tanaji** » 01 Oct 2010 19:10

http://blogs.forbes.com/firewall/2010/0 ... satellite/

Correlation only, does not mean causation

Thomas Kolarek · Post by **Thomas Kolarek** » 02 Oct 2010 00:50

Did The Stuxnet Worm Kill India’s INSAT-4B Satellite? from The Firewall by Jeffrey Carr
India should investigate this.

Shankar · Post by **Shankar** » 02 Oct 2010 12:27

no the problem was with solar panels and power distribution bus -nothing to do with Chinese - and the source is pucca

ramdas · Post by **ramdas** » 02 Oct 2010 12:34

Shankar,

For a total lox+kero. flow rate of 550 kg/sec I would expect 400 kg/sec lox and 150 kg/sec kero...at least this is the ratio for most russian lox/kero engines....Also. this is compatible with Ox. rich preburner and LOX pump discharge pressure of 400 bar.. otherwise, preburner gas (ox rich) temperature will be too high...fuel rich cycle with kero. has many difficulties like soot generation, etc...

Shankar · Post by **Shankar** » 02 Oct 2010 12:59

Ramdas - the chai walla was quite reliable

but understand what u r saying - shall go have some chai and see if he tells me more exact figures in a few days time

in the meantime shall check if can find some more details of similar sized lox cryo engine -stand by

Shankar · Post by **Shankar** » 02 Oct 2010 13:15

This is what I found
the oxidizer to fuel ratio in closed loop is 2.6 and in open loop is 2.2 -the combustion chamber pressure is 250 bar for RD 175 in our case slightly less as per information available

If we calculate using this ration we do get the figures Ramdas mentioned that is 400kg/sec lox and 150 kg/sec kerosene .And a chamber pressure of around 250 bar and calling for a turbo pump discharge pressure of close to 400 bar

corresponding fuel consumption is 2.5 tons /sec
and specific impulse 337 in vacuum compared to 400+ for full cryo engine like c-25

estimated burn duration 140 sec

Thanks Ramdas once again for the correction shall try to confirm from a few books on propulsion that I have - me not a propulsion guys boss:-)

ramdas · Post by **ramdas** » 02 Oct 2010 13:54

Shankar,

For RD-170 lox pump discharge press. is aprox. 600 bar.... 250 bar chamber press. is very high for Lox/Kero. It took the USSR 12 years to do even after they had experience with N2O4/UDMH engines at 200-230bar chamber pressure (RD-264/268)...they used these to develop in 2-3 years experimental engines with 180-200 bar chamber pressure...and 10 more years to do RD-170 from there....

In our case, after reading about this USSR story, I would say chamber pressure of 180-200 bar is very good and we would take 8-10 yrs or so to do this...if it is in the 250 bar range, or even close, it would be longer...400 bar pump discharge pressure is reasonable for 180-200 bar chamber pressure...not close to 250bar...

P.S: If you feel we should not discuss this, I will delete these posts...

Shankar · Post by **Shankar** » 02 Oct 2010 14:02

Ramdas - that is the problem developing even the pipelines for LOX at 300/400 bar whole set of components need be developed from basics including perfection and weld quality control which will stay good at liquid oxygen temperature
and the flow is second big problem the complete set of heat exchangers used to sub cool liquid oxygen and cool helium for testing purpose they are HUGE like I said about 10 times bigger at least than what have done so far
becasue we may not be going for cluster engine initially fed by common turbo pump the discharge pressure and flow requirement of turbo pumps is less but by how much shall find out
whole new concepts need be explored and tried out like cluster of high pressure tanks in common vacuum jacket etc - sure it will take time

Kailash · Post by **Kailash** » 06 Oct 2010 13:58

Chandrayaan-1's Startling discovery

AFTER the discovery of water on the moon – in the upper layers of its surface and in its atmosphere – Chandrayaan-1, the Indian moon mission, has now come up with another startling result: The atmospheric pressure on the sunlit side of the moon is about 100 times more than that expected from the night-time measurements made by the Apollo missions. This significant increase is substantially because of the presence of carbon dioxide (CO2) and water in the lunar atmosphere at intriguingly high concentrations.

While there may be an explanation for the water in the lunar atmosphere given the evidence for its presence on the moon from the other experiments on board Chandrayaan-1, the presence of significantly high levels of CO2 is a mystery. What is required are a confirmation of these levels by future experiments, including the follow-up mission Chandrayaan-2, and a viable explanation for them.

This puzzling discovery comes from one of the experiments on the Moon Impact Probe (MIP), the 35-kilogram sub-satellite that rode piggyback on Chandrayaan-1 and was made to crash on a spot near the lunar south pole. The relevant data were produced by the instrument called Chandra's Altitudinal Composition Explorer (CHACE).

While there was no ambiguity in the values for the night-time atmosphere, there has been a major gap in scientists' understanding of the daytime atmosphere. Thus, measurements made by CHACE, which provide the first data on the daytime lunar atmosphere, are a step towards filling that gap

A striking result of the spectra taken during the 24-minute descent is the presence in significant quantities of a large number of species in the mass range of 1 to 100 amu. The most dominant species correspond to 18, 44 and 28 amu, which are water, CO2 and nitrogen (N2) or carbon monoxide (CO) respectively.

But there is a lot of skepticism in the scientific community on the accuracy of values reported by CHACE.

Shankar · Post by **Shankar** » 07 Oct 2010 16:04

DEVELOPING THE INDIAN SEMI CRYOGENIC ENGINE -1

The performance of Russian lox kerosene engines are always better than equivalent American engines and the reason lies in higher chamber pressure
Which allows for a higher (geometric) expansion ratio and hence a higher exhaust velocity. The higher chamber pressure is possible, because the Russians apply a closed cycle system to drive the pumps, whereas the US designs are based on a gas-generator cycle. The latter essentially is an open cycle meaning that the turbine drive gases of the pumps are dumped separately, without using it to provide thrust (at least not in an optimal way). In contrast, in a closed cycle system the (cool) turbine drive gases are fed to the combustion chamber thereby allowing these gases to be used again, but this time to produce thrust.

Oxidizer: Lox. Oxidizer: LOX. Fuel: Kerosene. Fuel: Kerosene. Propellant Formulation: Lox/Sintin. Propellant Formulation: LOX/Kerosene. Optimum Oxidizer to Fuel Ratio: 2.56. Temperature of Combustion: 3,670 deg K. Ratio of Specific Heats: 1.24. Density: 1.02 g/cc. Characteristic velocity c: 1,805 m/s (5,921 ft/sec). Isp Shifting: 301 sec. Isp Frozen: 286 sec. Mol: 23.30 M (76.40 ft). Oxidizer Density: 1.140 g/cc. Oxidizer Density: 1.140 g/cc. Oxidizer Freezing Point: -219 deg C. Oxidizer Freezing Point: -219 deg C.. Oxidizer Boiling Point: -183 deg C. Fuel Density: 0.806 g/cc.. Fuel Freezing Point: -73 deg C.. Fuel Boiling Point: 147 deg C. Fuel Boiling Point: 147 deg C.
Specific impulse: 353 s.
Specific impulse sea level: 300 s

The closed cycle system was first implemented by the Russians around the 1960-s. The reason that the Russians were able to use a closed cycle design, is because at that time they had developed the technology, i.e. the materials, necessary to use oxygen-rich combustion gases from the pre-combustor to drive the turbopump(s), whereas in the USA NASA for long held the view that the use of oxygen-rich turbine drive gases induces corrosion problems. Lately, this view is shifting since there are a significant number of materials available today that are fully capable of being used as turbine components in hot oxygen-rich gases for service lifetimes of many hours.
Notice that the reason to use oxygen-rich turbine drive gases in a closed cycle LOX-kerosene system is because the kerosene propellant is also used as coolant, with maximum coolant temperatures being limited to about 490 K to prevent varnish deposits.

The RD-170 is a significant engine with the highest thrust achieved in any engine in the world.7904 kN ibf in vacuum and 7256 kN at sea level at a chamber pressure of 250 bar.It has four gimbaled thrust chambers , a single large 14500 rpm turbo pump ,two booster turbo pumps and uses staged combustion cycle with two pre burners.The pre burners operate oxy rich and burn all the oxygen and some of the fuel.The booster turbo pump allows lower propellant tank pressure thereby saves inert tank weight higher shaft speed of the main turbo pump and provide a higher margin against cavitations in main turbo pump impellers. The turbine of the fuel booster pump is driven by fuel tapped off discharge of the main fuel pump and the turbine of the oxidizer booster pump is driven by oxygen rich pre burner gas which is tapped off the turbine exhaust manifold and cooled with helium in a separate heat exchanger .The oxidizer rich gas flow to oxidizer booster pump is condensed or dissolved in liquid oxygen ,which then flows into main oxygen pump.
The helium subsystem supplies inert gas to actuators and control valves and purges .
Ignition is by injection of hypergolic fuel slugs from separate containers into two pre burners, vernier thrusters and the four thrust chambers

The Indian semi cryogenic engine to start with will have a single thrust chamber and a modest 200 bar chamber pressure ( as of today’s design ) and a 2000kN thrust nominal at altitude

SriSri · Post by **SriSri** » 09 Oct 2010 16:55

India to Launch Multiple Military Satellites in Coming Years reveals senior official

prashanth · Post by **prashanth** » 09 Oct 2010 18:06

^

Saraswat said India has already launched some satellites under this programme.

RISAT?

nrshah · Post by **nrshah** » 09 Oct 2010 18:26

^^^

VKS (as reported by DDM) said multiple already launched (Some Satellites)

RISAT is only one of them... wonder what are others?

D Roy · Post by **D Roy** » 09 Oct 2010 18:55

TES, Cartosat 2, 2A and 2B

Even Oceansat 2 comes in handy.

nrshah · Post by **nrshah** » 09 Oct 2010 19:30

thanks Roy...

What can be the role of oceansat for military purpose? As I understand it is to study ocean, climate and fish resources...

D Roy · Post by **D Roy** » 09 Oct 2010 19:39

studying the ocean, climate and fish has military utility too

...

think bathymetric, think ASW , think navigation ...

Shankar · Post by **Shankar** » 09 Oct 2010 22:56

There are 10 active Indian remote sensing satellites in operation - IRS- 1C, IRS-1D, IRS-P3, Oceansat-1/2, Resourcesat-1, CARTOSAT 1/2 and the Technology Experiment Satellite (TES). Another 680 kg Cartosat 2B costing $ 40 mill was successfully launched by the Polar Satellite Launch Vehicle (PSLV C-15) on 12th July 2010. They are all placed in 650 to 820km polar sun-synchronous orbits, carrying multiple cameras, which include Panchromatic Camera (PAN), Linear Imaging Self Scanner (LISS-III) and Wide Field Sensor (WiFS).

The satellites are intended for advanced mapping and intelligence applications. Cartosat-2B has a spatial resolution of 2m and a swath of 30 km per camera. The cameras are mounted with a tilt of +26 deg and -5 deg along track with respect to nadir to provide stereo pairs of images for generation of Digital Terrain Models (DTM)/Digital Elevation Models (DEM) with a revisit capability of 5 days, which can be realized by steering the spacecraft about its roll axis by +26 degrees.

Some of the military technologies were demonstrated in TES with military funding. These included attitude and orbit control system, high torque reaction wheels, new reaction control system with optimized thrusters and a single propellant tank, light weight spacecraft structure, solid state recorder, X-band phased array antenna, improved satellite positioning system, miniaturized TTC and power system and two-mirroron- axis camera optics. TES also carries a panchromatic camera with a spatial resolution of 1m, and an experimental radar.

The Svalbard and Tromso stations of Kongsberg, Norway have been added to the ISRO network to support data reception requirements of IRS missions.

On 23rd September 2009, ISRO in a landmark event launched an oceanmonitoring satellite OCEANSAT-2 and six European nano satellites aboard a Polar Satellite Launch Vehicle (PSLV) that lifted off from the Satish Dhawan Space Centre on India’s Southeastern coast. Prime Minister Manmohan Singh, in a statement, congratulated the (ISRO) on the successful launch of Oceansat-2, which he said “will herald a new beginning in our understanding of the oceans.”

Oceansat-2 was placed into its intended 720-kilometer sun synchronous polar orbit, dedicated to data collection that began with Oceansat-1, which was launched in 1999 and is nearing the end of its operational life. A third satellite, Oceansat-3, is planned for launch in 2012. Oceansat-2 is being used for weather tracking and forecasting and the identification of potential fishing zones, ocean condition forecasting, coastal zone studies and providing inputs for weather forecasting and climate studies. The Indian Navy has access to the data for bathymetric studies, to assist Anti Submarine Warfare (ASW) among other military uses.

Oceansat-2 for ocean surveillance carries an Ocean Colour Monitor (OCM) and an 8-band multi-spectral camera operating in the Visible Near IR spectral range and a Ku-band Pencil Beam Scatterometer. This camera provides an instantaneous geometric field of view of 360m covering a swath of 1,420 km. The Scatterometer is a microwave radar for measuring the ocean surface wind velocity. It operates at 13.515 GHz providing a around resolution of 50 m.

The Armed Forces intelligence agencies, and the tri-service Defence Image Processing and Analysis Centre (DIPAC) in New Delhi’s which has a satellite receiving centre at Gwalior, supports the Armed Forces by analyzing satellite data. The remote sensing LEO satellites are tiltable, can change their area of coverage and have resolutions from 25 meters to 1 metre but are blind in cloud cover or at night, and have a limited ability to detect targets at sea. On 20th April 2009, ISRO launched RISAT-2, India’s first satellite with Synthetic Aperture Radar (SAR) bought from IAI of Israel. Incidentally, it was hurriedly launched post the 26/11 terror attack on Mumbai, while RISAT-1 was being readied by ISRO.

This has demonstrated ISRO’s ability to launch spy satellites at short notice.

RISAT-2 has panchromatic cameras and radar capability similar to Israel’s TECSAR for imagery at sea and along the coast. RISAT-2 can penetrate clouds and is a milestone achievement.

It was indicated at an International Geo-Intelligence conference held in New Delhi in May 2010 that the ISRO and National Technical Research Organisation (NTRO), an intelligence agency modeled after USA’s National Space Agency (NSA), can control the satellites in coordination with the Armed Forces tasking and specially cater to the Navy’s requests. Adequate commercial data banks of ships and computer systems are now available commercially to finger-print ships at sea and in harbours. With space data now readily available 24x7, a repeat of the intelligence failure like the Kargil infiltration by Pakistani forces in 1999 can be well avoided, and greater surveillance of the Indian Ocean will also be possible.

http://www.indiastrategic.in/topstories717.htm

Satellites are like computers - u can use as u need -to scan face book or do 3d modeling of a thermonuclear explosion,to broadcast TV program kaun banega krorepati or set up instantaneously a secured digital fata link ,provide mid copurse correction to missiles ,to take high resolution images of military installations , missile launch warning etc etc

the complete list of payload is never disclosed - so the true military potential of any satellite can only be guessed

Shankar · Post by **Shankar** » 09 Oct 2010 23:03

Defense Electronics Research Laboratory (DLRL), a unit of the Defence Research Development Organisation (DRDO), is developing a dedicated network-centric communication intelligence satellite for detecting conversations and espionage activities in the region.

The existence of the project was revealed on Tuesday, February 2010 by DLRL director G. Bhoopathy.

"We are in the process of designing and developing a spacecraft fitted with an intelligent sensor that will pick up conversations and communications across the borders," he told reporters in Bangalore before the start of the first international conference on electronic warfare (EWCI 2010).

"The satellite fitted with the electronic sensor will be more powerful than the remote sensing satellites (IRSA) of ISRO. The spacecraft should be ready for launch by 2014," he added.

The Rs.100 crore satellite will be developed in partnership with the Indian Space Research Organisation (ISRO) and launched in the lower earth orbit — about 500 km above the earth — on board the polar satellite launch vehicle (PSLV) from Sriharikota spaceport in Andhra Pradesh, about 80 km north-east of Chennai.

http://knol.google.com/k/indian-space-projects#

Shankar · Post by **Shankar** » 09 Oct 2010 23:06

The first dedicated IAF satellite is scheduled for launch in FY 2011-12, after the Navy satellite scheduled for launch in FY 2010-11, according to TOI.

The satellite was initially scheduled to be launched in July 2009, according to a PTI report on November 18, 2008. In early January 2009, the IAF Chief said the IAF satellite will be launched in 2010.

According to IAF Chief Fali H. Major, the satellite will serve as the air force's eye in the skies. It will link up the six AWACS that the IAF is acquiring with each other as well as other ground and airbased radars.

http://knol.google.com/k/indian-space-projects#

Gaur · Post by **Gaur** » 09 Oct 2010 23:06

Shankar wrote:<snip>...Satellites are like computers - u can use as u need -to scan face book or do 3d modeling of a thermonuclear explosion...<snip>

How would you scan facebook using a satellite? And I am pretty sure that 3d modelling has nothing to do with satellites!

Austin · Post by **Austin** » 09 Oct 2010 23:09

^^ He means computers

Its good we are developing ELINT sats should be our ears for this region.

Bade · Post by **Bade** » 10 Oct 2010 03:00

Gaur wrote:
Shankar wrote:<snip>...Satellites are like computers - u can use as u need -to scan face book or do 3d modeling of a thermonuclear explosion...<snip>
How would you scan facebook using a satellite? And I am pretty sure that 3d modelling has nothing to do with satellites!

Satellite based remote sensing is not what is being made out to be the last few posts. It is one thing to take broad swath true color imagery within a few days of launch and declaring that everything is textbook perfect, but to extract more meaningful information takes many months of mission life to calibrate the sensors in orbit to get reliable information. Besides, all this needs to be done for the entire mission life of the satellite. You cannot define new missions and applications on the fly either.

Shankar · Post by **Shankar** » 10 Oct 2010 09:38

all remote sensing operation is bit of art and each sensor need calibration and re calibration to get effective data out of it in a meaningful near real time basis - agree its not like putting a camera on board and taking digital snaps

But on the subject - a funny incident comes to mind - remember the moon impact probe video -the video recorder used was actually a sony camcorder upgraded to mission standard by change of some electronics by SAC and performed very very well
- so everything need not be very complicated also

sarabpal.s · Post by **sarabpal.s** » 10 Oct 2010 14:59

http://www.atimes.com/atimes/China/LJ09Ad01.html

Lost Asian satellites send powerful signals

During the second half of 2010 all three Asian space powers - China, India and Japan - suffered major satellite failures. Each failure is significant, but for different reasons. In this instance, the satellite failures will be addressed in chronological order.

At the same time, it must be emphasized that satellite failures happen rarely.

What makes the loss of India's Insat-4B in early July - the first Asian satellite on this list - so important is the possibility that the satellite fell victim to deliberate act of sabotage as the result of a cyber attack. This involves the very malicious "Stuxnet" worm.

Shankar · Post by **Shankar** » 10 Oct 2010 15:34

nothing like that happened -it was solar power collection and distribution problem

sarabpal.s · Post by **sarabpal.s** » 10 Oct 2010 21:03

Shankar wrote:nothing like that happened -it was solar power collection and distribution problem

How

back up your comments

Like back door diplomacy, this thing is really something in large prospectus.

We may never know what government know if such a matter is real.

Shankar · Post by **Shankar** » 10 Oct 2010 21:13

well this aspect I know - how the power management software went haywire because of less than required availability form solar cells - the sats are much much protected against any kind of virus attack - now u tell me what makes u think it is possible to infect operating software of a sat when you dont know the high security multiple encrypted access code in the first place

actually asked a well known chaiwalla specifically this question dew days back and he was sure it was nothing like what is being floated around

sum · Post by **sum** » 10 Oct 2010 22:22

^^^ Interesting, heard a similar story as Shankar from my Chai-wallah...

Austin · Post by **Austin** » 11 Oct 2010 09:14

Shankar wrote:now u tell me what makes u think it is possible to infect operating software of a sat when you dont know the high security multiple encrypted access code in the first placea

Shankar , what kind of OS do sats use , are they general purpose Linux type OS customised to do specific task or are they proprietary RT OS ?