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India is building a spacecraft for mobile applications that will enable use of satellite phones without dependence on foreign players, a top space scientist said here on Monday.
Presently, satellite phones used in India are supported by foreign satellites, including Indonesian ones.
“We are yet to make an impact on satellite-based mobile communication. But again there are plans to evolve such systems,” former ISRO chairman G. Madhavan Nair said.
“Designs are evolved. They (ISRO) are in the process of building the satellite,” he told reporters after addressing the India Semiconductor Association’s Vision Summit.
“It requires a huge deployable antenna on board. With that...with reasonable power, we can manage hand held communication systems. Maybe in a year or two, it (the satellite) will be up,” Nair said.
He said only the S-band can be used for mobile applications. “Already ISRO is doing some work on that...almost like PC (Personal Computer) size,” the scientist said.
Bangalore, Feb 4 (PTI) India would shortly launch Cartosat-2B, a high-resolution remote sensing satellite, that would aid in infrastructure and urban planning, Indian Space Research Organisation Chairman K Radhakrishnan said today.
The launch was expected by March end or mid-April and the exact date would be finalised at the mission readiness review (MRR) meeting on February 10, he told reporters here.The satellite, which would be launched by Polar Satellite Launch Vehicle (PSLV), has a 0.8 metre resolution. This makes it capable to even take pictures of a car on the ground.
"Basically, it's a high resolution satellite," he said.
India launched Cartosat-2 in January 2007 and Cartosat-2A in April 2008. Cartosat-2B would add to the capability of the first two satellites.
"The advantage is when you have three satellites, you get more coverage in a day from different locations
is this a single GEO sat or LEO constellation similar to Iridium, but lesser in numbers covering only Asia?shravan wrote:India building spacecraft to enable use of satellite phones
Indian Space Research Organisation Chairman K. Radhakrishnan on Monday said the flight- testing of the indigenous cryogenic stage of the GSLV D3 would be conducted in April.
Remnant tubular structures or tunnel-like formations from lunar volcanic flows in the past, which extend a couple of kilometres on the moon’s surface, could serve as ideal landing as well as human settlement sites for future missions, including Chandrayaan-II, according to some new findings from India’s Chandrayaan-1.
Bangalore, Feb 9 (IANS) India is set to develop a dedicated network-centric communication intelligence satellite for detecting conversations and espionage activities in the region, a top defence scientist said Tuesday.
“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,” Defence Electronics Research Laboratory (DLRL) director G. Bhoopathy told reporters here.
The Rs.100 crore (Rs.10 billion) satellite will be developed in partnership with the state-run 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.
“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,” Bhoopathy said on the margins of a preview on the first international conference on electronic warfare (EWCI 2010).
The Hyderabad-based DLRL, which functions under the aegis of state-run Defence Research Development Organisation (DRDO), is also developing a border network-centric electronic warfare sensor for surveillance on the Indian borders in the mountain range and desert areas.
“The electronic warfare (EW) sensor will be located on the mountain range facing Pakistan, China, Nepal and the northeast to detect troop or vehicular movement across the borders. Some of the sensors can also be deployed in the plains or desert for monitoring the ground situation in border areas,” Bhoopathy said.
Code-named “Divya Drushti” (foresight), the radars will be installed on the mountain tops from December this year onwards.
This reminds me of an automobile ad coming on tv now-a-days which says If you have power, you need not show it.shravan wrote:India to build intelligent satellite for surveillance
To quote Sun Tzu: "All War is deception".Venu wrote:This reminds me of an automobile ad coming on tv now-a-days which says If you have power, you need not show it.shravan wrote:India to build intelligent satellite for surveillance
Why can't we Indians do anything secretly and tell out only when it is operational for some time?
What duration of coverage will such a satellite have over say pakistan and eastern and western china? Not more than a couple of hours a day. And revisit time over a specific geographic area will be once in a few weeks unless the satellite constantly reorients its antennas all the time.shravan wrote:India to build intelligent satellite for surveillance
I'm not a space expert but I don't quite understand what you are asking exactly. "Stationary" in space is a relative term and your question seems to elude that you don't really understand the nuances.jaladipc wrote:Is it possible to have a sat in stationary orbit for extended periods of time without burning fuel?
Lets say we want to keep and eye on porki land for example,and launch a RISAT/CARTOSAT dedicated for pakistan(parked at an altitude of some 1000km) to monitor every nook and corner with a vectoring camera/radar.
TAMBARAM: Indian Space Research Organisation Chairman K. Radhakrishnan on Monday said the flight- testing of the indigenous cryogenic stage of the GSLV D3 would be conducted in April.
The vehicle would carry GAST-4, a communication satellite, he told reporters after receiving an honorary degree of Doctor of Science during the 5th convocation at the SRM University in Kattankulathur.
“Though we had several GSLV flights, we were using the Russian cryogenic stages,” he said. As far as cryogenic engine and stages were concerned, ISRO had tested engines for 7,500 seconds.
“We have qualified the stage. The entire stage was filled and fired for its entire duration of 720 seconds at [the Liquid Propulsion Centre in] Mahendragiri in Tamil Nadu and it was very successful,” Dr. Radhakrishnan said.
India is set to develop a dedicated network-centric communication intelligence satellite for detecting conversations and espionage activities in the region, a top defence scientist said on Tuesday.
“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,” Defence Electronics Research Laboratory (DLRL) director G. Bhoopathy told reporters here.
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....
since I am not an orbital expert,I discount my altitude corrections.Brando wrote:I'm not a space expert but I don't quite understand what you are asking exactly. "Stationary" in space is a relative term and your question seems to elude that you don't really understand the nuances.jaladipc wrote:Is it possible to have a sat in stationary orbit for extended periods of time without burning fuel?
Lets say we want to keep and eye on porki land for example,and launch a RISAT/CARTOSAT dedicated for pakistan(parked at an altitude of some 1000km) to monitor every nook and corner with a vectoring camera/radar.
To answer you first question, yes. I think you are talking about the Geostationary Earth Orbit. To answer your second question, the basic principle is the higher the orbit the greater the orbital period and the lower the orbital velocity (since orbital velocity squared is inversely proportional to the altitude). So at 1000 kms you would typically have a smaller orbital period (time taken to complete one rotation) and higher "orbital" velocity than at Geostationary Earth Orbit. Thus you could achieve a "forced geosynchronous orbit" by firing some kind of thrusters to both reduce your angular velocity drastically while maintaining the same altitude (and prevent re-entry). This is how surveillance satellites maneuver to observe specific locations. Theoretically this can be done indefinitely by some form of Solar sail or with a ground-tether but practically this has never been accomplished.
There is only one orbit that provides same orbital velocity relative to spin of the earth -- that is the geostationary orbit, about 36,000 Kms above the earth. Also note that *being* in geostationary orbit does not guarantee that the satellite will be stationary wrt to the earth. The orbital inclination should be 0 degrees. Else the satellite will draw a "8" in the sky (over the same place though).jaladipc wrote:since I am not an orbital expert,I discount my altitude corrections.
In any technical term,and that too regarding sats? stationary means its relative to a point on the earth.
While all orbits have their own velocities depending on their perigee/apogee whatever........,stationary orbits theoritically offer 0 orbital velocity9 in a sense that the body in that orbit moves with the same angular velocity relative to the spin of earth hence providing a stationary point of view to a point on the ground.
I think I made myself clear with stationary orbits.Now wondering which orbits provide same orbital velocity relative to the spin of earth?
Bangalore: Indian Defence Research Agencies, including DRDO were working out to develop a Communication Intelligence Satellite, module, for Indian Arm Forces for Surveillance in its borders, Dr U K Revankar, Director Defence Avionics Research Establishment (DARE), said here today.
Speaking to newsmen Dr Revankar said that the Communication Satellite 'Comtel' would be launched by Indian Space Agency, ISRO in the next four to five years.
He said the Satellite module, which would be developed in co-ordination with the all the Indian Defence Research Agencies including DRDO would serve Indian Arm Forces to gather Intelligence captivities in the International border.
He said that the proposed Satellite would be place din the skies with the Low Orbit distance of about 500 KM would not only intercept communication but also pick up Radar based signature.
Great find..negi wrote:For those interested in Jingogiri.
This page has almost complete info on all of the ISRO's launch vehicles.
India's space launch vehicles
Cryogenic stage and the payload itself.Varoon Shekhar wrote:Yes, and it would also be nice to know what specifically is holding up the launch of the GSLV Mark-2, with GSAT-4. Did they find an unforeseen difficulty with the cryogenic engine/stage?
no problem with cryogenic engine -it has been qualified fully -some additional tests/procedures before launch - it will go in April as of nowYes, and it would also be nice to know what specifically is holding up the launch of the GSLV Mark-2, with GSAT-4. Did they find an unforeseen difficulty with the cryogenic engine/stage?
Since ISRO has ANTRIX corp. Why not use it to better the brand?harbans wrote:^^ Vyomagami sounds cool. Better than Vyomanaut or gaganaut.
Looks like wrong reporting.The first flight testing of GSLV MK-III rocket, which will put heavier satellites in space, is likely to be carried out in April, the ISRO said on Wednesday.
ISRO Chairman K. Radhakrishnan said scientists are working hard in developing the satellite and expressed hope that its first flight testing would take place in April.
they mean MkII I think.
The tubelight just chamkofied!Pulikeshi wrote: Since ISRO has ANTRIX corp. Why not use it to better the brand?