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PSLV-C37 Successfully Launches 104 Satellites in a Single Flight

isro.gov.in

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Re: PSLV-C37 Successfully Launches 104 Satellites in a Single Flight

#13

Post by sureshn »

PSLV is undoubtedly among the cheapest launch vehicles (the cost includes that of PSLV-XL variant, other variants are even cheaper). The launch contracts are usually negotiated according to price per kg of payload to the orbit. Given that the estimated value of the space industry today is around ~$200 billion, ISRO should charge higher price for foreign country satellites it launches through its subsidiary Antrix. ISRO is the jewel in the crown for India and congratulations to all those wonderful scientists who are making India proud.

Re: PSLV-C37 Successfully Launches 104 Satellites in a Single Flight

#18

Post by shripadk »

arjie wrote: post #17

What's the hard part about deploying multiple satellites? Is it making sure they reach different orbits or is it just carrying them or something else?

The hardest part is in ensuring that the satellites are launched in different directions to avoid them colliding when being deployed in orbit. These satellites have to be in the same orbit but with increasing distance between them.

From what I understand, these satellites were injected into the heliosynchronous orbit (https://en.wikipedia.org/wiki/Sun-synchronous_orbit) at different slots, different angles and at different times.

However, the sole idea behind deploying 104 satellites is not to create a record of some sort but to utilize the maximum capacity of the workhorse rocket (PSLV). This results in greater ROI for the Space Agencies (Antrix / ISRO) as most of these 104 satellites (101 I think) were foreign satellites.

According to this article: http://tech.firstpost.com/news-analysis/isro-to-recover-half... ISRO will recover half of the total cost incurred for the launch from foreign satellites mounted on the PSLV.

Re: PSLV-C37 Successfully Launches 104 Satellites in a Single Flight

#19

Post by swatkat »

arjie wrote: post #17

What's the hard part about deploying multiple satellites? Is it making sure they reach different orbits or is it just carrying them or something else?

One of the challenges is to pack all those satellites in launch vehicle's payload adapter. The payload adapter on launch vehicle needs to be flexible enough to allow such varying number of payloads. In this mission, ISRO had to realize a new/modified payload adapter to carry those 104 satellites.

Next is to accurately inject all those satellites - either into their respective orbits if it's a multi-orbit mission, or with sufficient time gap and re-orientation between injections if it's a single-orbit mission.

This was a single orbit mission (all sats released into SSO). So, PSLV's 4th stage had to time those 104 satellite injections. It also need to re-orient itself for each injection depending on satellite's requirement. This mission had as many as 103 "separation events". All this logic is pre-programmed and executed by launch vehicle's onboard computer.

Check out QuadPacks lined up before the launch: http://blog.isilaunch.com/the-quadpack-line-up/

And, check out those QuadPacks mounted on PSLV payload adapter around primary payload: https://imgur.com/a/LM9Cp

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