India to use PSLV 4th stage for orbital research and docking tests

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The new colonial movement: India’s space agency ISRO now plans to conduct research, including docking tests, using the 4th stage of its PSLV rocket following normal commercial operations.

The PS4 is the last stage of the Polar Satellite Launch Vehicle (PSLV) rocket, which until now used to go waste after putting the spacecraft into the desired orbit. ISRO, in the last two attempts tried to keep PS4 alive in space, and was successful. As the next step, it has now called for experiments from national and international institutions. The experiments will cover six areas, including space docking

“The PS4-Orbital Platform (PS4-OP) refers to a novel idea formulated by ISRO to use the spent PS4 stage (fourth stage of PSLV) to carry out in-orbit scientific experiments for an extended duration of one to six months. The advantage being the stage has standard interfaces & packages for power generation, telemetry, tele-command, stabilization, orbit keeping & orbit maneuvering,” Isro said on Saturday.

All of this is engineering research, finding ways to operate in space effectively. More important, they are doing what SpaceX does, letting their commercial operations pay for their research and development. Rather than fly separate missions to do these engineering experiments, they will let their commercial customers pay for it.



  • wodun

    This is pretty cool. Northrup Grumman does this with Cygnus to some degree but so far all of the talk of using upper stages for wetrooms and workshops and whatnots has all been just talk.

  • Edward

    wodun wrote: “Northrup Grumman does this with Cygnus to some degree but so far all of the talk of using upper stages for wetrooms and workshops and whatnots has all been just talk.

    The largest problem that potential commercial space stations have is a lack of access to them on orbit. Right now, the only providers of manned launch vehicles are governments, and neither of them seem able to use them for access to commercial space stations. Last year’s problems lead me to think that Russia may be overwhelmed just by sending people to the government-run International Space Station (ISS), and China may not be available for access to U.S. commercial space stations.

    What Northrup Grumman, Bigelow, Ixion, and Axiom are waiting for is the upcoming commercial manned launch vehicles from the Commercial Crew Development program (CCDev). I have heard some speculation that NASA intentionally slows development of CCDev because it does not want to be shown up by commercial manned launch for being so slow with Orion-SLS, but I have not heard much about NASA not wanting competition for ISS.

    News like this suggests that not just commercial companies are serious about competing with ISS but that there are countries that want to do so, too. Hopefully, NASA will relent and allow commercial manned launches sooner rather than later, because this will allow commercial space stations to begin operations a couple of years later. Maybe some of those countries will be able to buy or lease some of those commercial space stations for their own use, using commercial launchers to man and supply them.

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