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China's Moon mission sees first seeds sprout

bbc.com

111–120 of 164 posts

Re: China's Moon mission sees first seeds sprout

#111
post #20

Earlier quoted context omitted.

is this kind of simulated gravity sufficient for the convection processes described?

I think Einstein might have something to say about that one. https://en.wikipedia.org/wiki/Equivalence_principle

Linear acceleration is equivalent to gravity. Spinning is not; it introduces the Coriolis psuedo-force or however you prefer to look at it, which allows it to be distinguished from gravity.

Re: China's Moon mission sees first seeds sprout

#112
post #98

Earlier quoted context omitted.

wait its not growing in a sample of regolith? i thought that was the point of the experiment (gravity experiments with plants have been done on ISS, no?)

No, the point is growing in lunar gravity. Things get confused and need training by light in microgravity. We really don't know what they do in lunar g; "it just works" is a great result. Boring but useful.

thanks, that makes sense, and experiments with lunar soil could (have?) been done on earth

Re: China's Moon mission sees first seeds sprout

#113

Earlier quoted context omitted.

What I heard is that we have data on plant growth on Earth (1G) and on the ISS (0G), but not at reduced gravity like on the Moon (.17G).

It would be easier to produce the .17G on the ISS (with a centrifuge) than putting these seeds on the moon.

That's so not the case (mostly for reasons of size) that the Germans are flying Eucropis as a separate mission right now. It will do spin-simulated lunar and mars g.

Re: China's Moon mission sees first seeds sprout

#114

Earlier quoted context omitted.

What I heard is that we have data on plant growth on Earth (1G) and on the ISS (0G), but not at reduced gravity like on the Moon (.17G).

It would be easier to produce the .17G on the ISS (with a centrifuge) than putting these seeds on the moon.

[deleted]

Re: China's Moon mission sees first seeds sprout

#115
post #21

> The plants are in a sealed container on board the lander. For a moment I thought they were in the open... Since they are enclosed is there a reason why they should not sprout? The gravity is less but that should not make a difference.

The temperature might be an issue. The moon surface 106°C during the day, -183°C during the night. Also, the sun is brighter in space than an Earth under the atmosphere. The long days and nights lasting 12 Earth days each might also be problematic.

They're in a controlled environment, not being baked and frozen. This is a test of the gravity only.

Test one thing at a time.

Re: China's Moon mission sees first seeds sprout

#116

To me it seems that the greatest obstacle to space colonization would be maintenance and production of materials and technology needed to sustain and expand the colony. Seems like the last step for truly becoming self sustaining. You'd need extremely small scale factories that can build everything needed for a modern civilization. I wonder what that would take. What the smallest amount of shipments and time would be.…

Mars is a better space body for a colony. I suggest reading "A case for Mars" by Robert Zubrin.

Re: China's Moon mission sees first seeds sprout

#117

Earlier quoted context omitted.

Shielding off radiation is hard too, on Earth you gave an atmosphere and a magnetosphere. On the Moon or Mars its much harder to do the shield effectively

There are some caves on the moon that provide shielding and, probably, water since they have perpetual shadow inside them. They can be very attractive places to build future colonies.

And if you don't have caves you can just pile dirt on top of your habitats. Dirt is one potential export from a lunar settlement. Everywhere outside the Van Allen Belt needs radiation shielding and dirt doesn't mind being violently accelerated in a mass driver.

Re: China's Moon mission sees first seeds sprout

#118
post #97

Earlier quoted context omitted.

There is no friction in space, so things can move much faster and stay there longer. Sending a drone to shitistan at 7.8 KM/second is impossible to do in Earth's atmosphere with today's technology. Likewise for keeping an object airborne for more than a few tens of hours. In space, things can move quickly and stay up there for quite some time. See also the high Delta-V experimental craft, such as the X-37, which allo…

> shitistan Seriously? This isn't 4chan.

That's funny, I really thought that I just coined the word. I guess that rule 34 really applies!

Re: China's Moon mission sees first seeds sprout

#119

Earlier quoted context omitted.

But why should you have a 100% complete industry, a colony can trade with Earth like countries trade with each other, a colony could trade some rare resources and buy high tech stuff. The main obstacle a colony will have is the initial buildings/bunker with all the life support and safety tech, plus extra redundancy and a backup plan if something bad happens there or on Earth . If the colony would manage to generate…

Sure, becoming 100% self sufficient wouldn't be a reasonable short term goal but I can't imagine there being any product worth trading in the long term over such distance and given such cost for logistics?

> over such distance and given such cost

The moon is just a few days away.

The costs are not a given. With new better tech, then can come waay down.

Also note that the freight ships need not be manned.

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