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Chang'e 6 lunar sample return mission returns with samples from moon's far side

theguardian.com

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Re: Chang'e 6 lunar sample return mission returns with samples from moon's far side

#61

Post by jandrese »

somenameforme wrote: post #30
JumpCrisscross wrote: post #4

Earlier quoted context omitted.

> nuclear power plans by Russia not so much Why? Any lunar base without nuclear power plans is not a serious effort.

The moon is fairly unique (relative to Earth) in that the exact same spot will go from -200C to +100C on a two week cycle (day and night). It seems "obvious" that there must be some clever way to exploit this to generate energy in a simple and novel fashion.

I have always assumed that the first moon colony would be on the north or south pole to avoid this issue. Not too hard to imagine a solar array set up to track the sun with a very slow rotation. The colony itself would be in a crater to avoid direct sunlight and provide a place to dump the heat from the solar array.

Otherwise the need to bring enormous power storage to handle the half month of darkness and bitter cold makes solar a bit impractical and the only other reasonable alternative is nuclear power.

The big problem with attempting to exploit the temperature differential is that it happens on such a slow cycle that the total amount of energy available is quite low.

Re: Chang'e 6 lunar sample return mission returns with samples from moon's far side

#62

Post by psadri »

scoot wrote: post #3

What are they expecting to be different about samples from the moon's far side to those previously collected?

It would be a good sci-fi plot to find a moon base hiding back there. Populated by aliens/your current enemy/tech billionaire mad scientist/high IQ octopi

It could also be an abandoned base.

Re: Chang'e 6 lunar sample return mission returns with samples from moon's far side

#63

Post by sudosysgen »

JumpCrisscross wrote: post #35
throwaway199956 wrote: post #10

One thing they seems to have got working fairly reliably is the lunar landing of the probe using image processing to guide the final approach and touch down. It seems to have worked well in this and the previous mission, there are videos on youtube of that. https://youtu.be/wUju9-cckKA?si=nZFOCga10mnCA_vs The other component is the autonomous docking of the return probe in lunar orbit. Soviets have done a lunar sampl…

> the lunar landing of the probe using image processing to guide the final approach Anyone building precision weapons has gotten fairly good at this.

It is a lot more difficult in space, since you don't have the atmosphere to steer for free and because fuel margins get very expensive. Being familiar with these image processing systems, I could see it being a significant challenge.

Re: Chang'e 6 lunar sample return mission returns with samples from moon's far side

#64

Post by sinxccc »

scoot wrote: post #3

What are they expecting to be different about samples from the moon's far side to those previously collected?

you won't expect rock samples from New England and middle east are the same, right? The current theory is that samples collected by Chang'e 6 could be the oldest sample we ever saw from Moon. It would be worth to study and prove that.

Re: Chang'e 6 lunar sample return mission returns with samples from moon's far side

#67

Post by pie420 »

itishappy wrote: post #36
somenameforme wrote: post #30

Earlier quoted context omitted.

The moon is fairly unique (relative to Earth) in that the exact same spot will go from -200C to +100C on a two week cycle (day and night). It seems "obvious" that there must be some clever way to exploit this to generate energy in a simple and novel fashion.

Good news! Thermal cycles are caused by the sun, and we can harvest sunlight directly! Storage is an issue...

Storage is not an issue. It's been solved for decades. In fact, energy storage is amazing and cheap now, thanks to smartphones and EVs. You can buy consumer level batteries for very very cheap.

Re: Chang'e 6 lunar sample return mission returns with samples from moon's far side

#68

Post by darkwater »

pc86 wrote: post #53
porphyra wrote: post #24

Earlier quoted context omitted.

Let's not bring sinophobia and geopolitics into a scientific mission to the moon.

No, but can we bring realism into it? The explorers may be exploring for the sake of it, but the people paying for it definitely aren't. Many - perhaps even most - of the people at NASA would have probably done the job for free if they were able, but the people allocating NASA's budget in the 50s and 60s were doing so for geopolitical reasons first and foremost.

So if it's "us" it's good, and if it's "them", it's bad?

Re: Chang'e 6 lunar sample return mission returns with samples from moon's far side

#69

Post by burnished »

psadri wrote: post #62
scoot wrote: post #3

What are they expecting to be different about samples from the moon's far side to those previously collected?

It would be a good sci-fi plot to find a moon base hiding back there. Populated by aliens/your current enemy/tech billionaire mad scientist/high IQ octopi It could also be an abandoned base.

Or your ancestors

Re: Chang'e 6 lunar sample return mission returns with samples from moon's far side

#70

Post by itishappy »

pie420 wrote: post #67
itishappy wrote: post #36

Earlier quoted context omitted.

Good news! Thermal cycles are caused by the sun, and we can harvest sunlight directly! Storage is an issue...

Storage is not an issue. It's been solved for decades. In fact, energy storage is amazing and cheap now, thanks to smartphones and EVs. You can buy consumer level batteries for very very cheap.

Battery tech is awesome, but I think you're overselling it a bit. We've barely started figuring out grid-scale battery storage on Earth. There's 2 big reasons the Moon is going to be much much harder:

1. Batteries are heavy, and space ain't cheap. Current launch pricing is about $1.5k/kg to LEO. The Moon will be more, it's further away. Even if Starship brings that down by a factor of 10, transportations costs are still going to be astronomical.

2. The day-night cycle on the Moon is slow. Your batteries are going to need to be able to store half a month worth of power. You'll need 15x more batteries on the Moon than you would on Earth.

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