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Chandrayaan-3 Soft-landing [video]

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Re: Chandrayaan-3 Soft-landing [video]

#341

Post by phanimahesh »

contrarian1234 wrote: post #289
thyrox wrote: post #47

Not asking rhetorically but why is this a big deal? Is it because it's going to the south pole? What are some other benefits to be gained from this?

I'd be curious if it's at all interesting from a technical perspective. It was impressive in the 60s and 70s because a lot of new things needed to be discovered and understood to make it happen. But now a days.. are there really technical aspects that would not be covered in a typical engineering course? I get it's very expensive and hence difficult to pull off - but this makes it comes off as mostly nationalism and…

The money used on these programmes doesn't burn up, it gets recirculated. As an Indian I consider this a pretty good use of tax payer money.

Re: Chandrayaan-3 Soft-landing [video]

#342

Post by oxygen_crisis »

shri_krishna wrote: post #142
throwaway_0823 wrote: post #110

Earlier quoted context omitted.

The guy is a megalomanic. The ISRO official who announced the successful landing even asked Modi to "bless us"! No doubt a diktat from Modi.

> The guy is a megalomanic The Prime Minister is the head of Department of Space, whose primary arm is ISRO. He is the boss. Literally every Prime Minister of India has attended ISRO launches and addressed ISRO after success/failure of launches. > asked Modi to "bless us" You probably aren't Indian but this is quite common in India where we seek blessings from elders.

I can't think of any other space mission that devoted one of the control room screens to projecting the head of state's face throughout the landing...

Re: Chandrayaan-3 Soft-landing [video]

#343

Post by itissid »

Congrats to all of the team at ISRO. Assuming the software development for these is non trivial; Its interesting that with the last mission(per Scott Manly) was designed to always select a spot(or more precisely a trajectory) and try hit it.

What made them make that decision? Was it like "lets be as precise as we can because we want to get to the spot X because X is special" and thus "Lets let the software always compensate for any errors to get to X". I am assuming that even at this point they tested the software for extreme conditions. It is most likely that once this assumption was made the Software was built that way, i.e: "Lets test the Software can always correct for any issues to get to X with feedback(like thrust)". It trades off Safety for Accuracy(to hit X).

This time the idea was "Lets select a trajectory to X" but this time "We will let the software prioritize safety(altitude, speed and heading) to be within norm once we start descending towards X". And additionally "Not make any corrections if we are somehow too far off X if it exceeds safety limits". It trades off Accuracy(to hit X) for Safety.

Re: Chandrayaan-3 Soft-landing [video]

#344

Post by tempnow987 »

kensai wrote: post #332
skynetv2 wrote: post #329

Despite all the sour comments trying to find fault and criticize, this is a remarkable achievement, especially on the heels of the failed Chandrayaan-2 mission. Congrats to the team!!! Just 4 years to recover from the failure and achieve a phenomenal success. India just keeps executing despite what others may say. The team deserves even more praise to be able to achieve these wins with limited resources.

And a very inexpensive/frugal attempt for that matter! It has been a miracle of cost effectiveness. This is a wonder on its own.

Really the true wonder! Compare this to the US's SLS plans! The budget is mindboggling.

Re: Chandrayaan-3 Soft-landing [video]

#347

Post by dotnet00 »

lenkite wrote: post #330
dotnet00 wrote: post #320

Earlier quoted context omitted.

Edit:nvm, I'm wrong, see below They've given out vague explanations such as a software glitch, while holding the detailed post-mortem back claiming the obviously absurd excuse of national security concerns. This is counter to how they typically operate as well as how most other agencies/companies around the world operate these days, where they at least explain what went wrong. eg Hakuto-R's team explaining that their…

Might want to update your general knowledge. The ISRO Chief explained this in an interview. It wasn't just passed off as "software glitch" with no explanation. Chairman S Somanath has given three main reasons that led to the crash-landing of the Vikram lander on September 6, 2019 just minutes before the touchdown. The ISRO chairman said, “The primary issues were: One, we had five engines which were used to reduce the…

Huh, I missed that, thanks for the info!

Re: Chandrayaan-3 Soft-landing [video]

#348

Post by mzs »

subtra3t wrote: post #101
mathieuh wrote: post #77

Wait did it land while they were showing us Modi's face? Why didn't they show the camera feed?

Maybe you were lagging? PM Modi's face wasn't displayed at the exact moment it landed, but it was shown before and after that moment.

No, the feed on the right switched to the animation from the lander's view at 19m above the surface.

Re: Chandrayaan-3 Soft-landing [video]

#349

Post by wheelerof4te »

BtM909 wrote: post #87
mathieuh wrote: post #77

Wait did it land while they were showing us Modi's face? Why didn't they show the camera feed?

They showed the animation. Maybe in case something went wrong, they didn't want to broadcast that?

Why? No transparency at all. Show me the images and the video of the Moon.

Every kid today can create an animation.

Re: Chandrayaan-3 Soft-landing [video]

#350

Post by shri_krishna »

oxygen_crisis wrote: post #342
shri_krishna wrote: post #142

Earlier quoted context omitted.

> The guy is a megalomanic The Prime Minister is the head of Department of Space, whose primary arm is ISRO. He is the boss. Literally every Prime Minister of India has attended ISRO launches and addressed ISRO after success/failure of launches. > asked Modi to "bless us" You probably aren't Indian but this is quite common in India where we seek blessings from elders.

I can't think of any other space mission that devoted one of the control room screens to projecting the head of state's face throughout the landing...

That might have been an issue with the control room getting the timing of the live feed wrong. No reason to read into it more than that. We have had previous missions where the Prime Minister's live feed was beamed after the event concluded
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