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Chandrayaan-3 Soft-landing [video]

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Re: Chandrayaan-3 Soft-landing [video]

#291

Post by ethbr1 »

rqtwteye wrote: post #282
Philip-J-Fry wrote: post #204

Earlier quoted context omitted.

SpaceX livestreams didn't get super popular for having a politician on them. They got popular for showing exactly what's happening with enthusiastic presenters narrating it. Most people find speeches and politicians boring. They wanna see rockets flying, robots moving, etc.

“enthusiastic presenters narrating it.” I seriously hate their narrators and all the cheering.

Last I heard, their narrators were regular SpaceX employees with day jobs. So somewhat understandable they have an emotional stake in mission success.

Re: Chandrayaan-3 Soft-landing [video]

#292

Post by layer8 »

hoseja wrote: post #126
m0llusk wrote: post #86

Earlier quoted context omitted.

If anything they seem to have overcorrected for this. This landing path stopped with a near hover at around 800m, then a prolonged hover at 150m while the lander scoped the situation, then an extremely slow descent that allowed for corrections the whole way down. Very impressive.

Also incredibly inefficient.

First make it work, then make it right, last make it efficient.

Re: Chandrayaan-3 Soft-landing [video]

#294

Post by vikingerik »

goku12 wrote: post #262
Rygian wrote: post #227

Earlier quoted context omitted.

That's an example of failing to follow the "Aviate, Navigate, Communicate" rule of thumb.

Could you elaborate how that applies here? Communication is out of the question - there's nothing the people on the ground can correct. And the lander apparently failed because it tried to navigate its way back to the designated landing site.

Communicate wasn't the important part, but you got it in your last sentence. It was trying to navigate over aviate - trying to get to its designated landing spot too hard so that it neglected/failed to stay airborne (spaceborne).

Re: Chandrayaan-3 Soft-landing [video]

#295

Post by renewiltord »

adolph wrote: post #272
pyeri wrote: post #242

Earlier quoted context omitted.

On the other hand, political speeches on such occasions go down as most remembered historically. The infamous quote "One small step for man, one giant leap for mankind." was obviously said by some politician! (or at least with non-technical motives)

> The infamous quote "One small step for man, one giant leap for mankind." What makes the quote in famous rather than just famous?

Could just be a misuse of infamous but could just as well be intended to refer to the fact that Man and Mankind mean the same. You need an article in front to transform "One small step for Man" into "One small step for a man" to refer to Neil himself stepping.

Re: Chandrayaan-3 Soft-landing [video]

#296

Post by goku12 »

vikingerik wrote: post #294
goku12 wrote: post #262

Earlier quoted context omitted.

Could you elaborate how that applies here? Communication is out of the question - there's nothing the people on the ground can correct. And the lander apparently failed because it tried to navigate its way back to the designated landing site.

Communicate wasn't the important part, but you got it in your last sentence. It was trying to navigate over aviate - trying to get to its designated landing spot too hard so that it neglected/failed to stay airborne (spaceborne).

That's much clearer. Aviate > Navigate. Thanks!

Re: Chandrayaan-3 Soft-landing [video]

#297

Post by tjpnz »

goku12 wrote: post #236
The_Colonel wrote: post #71

Earlier quoted context omitted.

Besides what others said, it gets extra spice from the fact Russia failed to do the same just days ago.

Russian space program is a shadow of what it once was. Their history is full of daring missions and extraordinary achievements. I wish they would engage in a space race than in a war.

Might be time for China to reconsider its role with Russia in future manned moon missions. Any prestige the Russian program once had has long since faded, even ground operations at Baikonur are now at risk with equipment being impounded by bailiffs from Kazakhstan to service billions in debt.

Re: Chandrayaan-3 Soft-landing [video]

#298

Post by Sharlin »

devnonymous wrote: post #173
hoseja wrote: post #143

Earlier quoted context omitted.

I was surprised they had the propulsion budget for it.

Not only was the Chandrayaan 3 budget lesser than that of Chandrayaan 2, as a meme doing the rounds point out, it was lesser than the budgets of some Hollywood blockbusters like Interstellar. So yeah, safe to say they could have had the budget for more if necessary.

"Fuel budget", "mass budget", "payload budget", even "delta-v budget" are common terms in spaceflight and refer to how much of a valuable thing a spacecraft can carry given some pesky laws of physics [1], nothing to do with money (except insofar as more money would let you build a bigger spacecraft…)

[1] https://www.kallmorris.com/columns/tyranny-of-the-rocket-equ...

Re: Chandrayaan-3 Soft-landing [video]

#299

Post by basementcat »

goku12 wrote: post #250
shubhamkrm wrote: post #212

Earlier quoted context omitted.

IIRC, he mentioned missions to the Sun, Venus and a manned space mission.

I really wish to see a lander mission to Venus. Doesn't look like anybody other than Russia has done it - that too nearly 40 years ago. The environment is so extreme that the technology - especially electronics - would have to be radically different. The data is also likely to be extremely interesting.

One of the probes from Pioneer Venus 2 (launched by NASA in 1978) briefly sent back data after impacting the surface of Venus. https://en.m.wikipedia.org/wiki/Pioneer_Venus_Multiprobe

Re: Chandrayaan-3 Soft-landing [video]

#300

Post by pavon »

ceejayoz wrote: post #178
TuringNYC wrote: post #163

Firstly - congratulations to the whole team on this achievement I'm also curious - Why the south pole of the moon? does it have an added significance vs other locations on the moon? - Is a landing on the south pole more difficult to achieve? Seems so according to this article: https://www.reuters.com/science/why-are-space-agencies-racin...

https://en.wikipedia.org/wiki/Lunar_south_pole > It is of special interest to scientists because of the occurrence of water ice in permanently shadowed areas around it. The lunar south pole region features craters that are unique in that the near-constant sunlight does not reach their interior. Such craters are cold traps that contain a fossil record of hydrogen, water ice, and other volatiles dating from the early S…

Chandrayaan 3 landed at around 69 degrees south latitude which isn't far enough south to access the permanently shadowed craters where large ice deposits might occur (and the Pragyan rover uses solar panels for power).

I haven't read specific reasons for choosing that site, but we have never landed that far south, and it will be interesting to see what differences (if any) there are from the more central latitudes, which is a good enough reason on its own.

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