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saagarjha

> It may also carry plant seeds and silkworm eggs, according to the official Xinhua News Agency.

Is there any scientific/experimental reason for this, or is it just a symbolic gesture?

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http://www.xinhuanet.com/tech/2017-06/13/c_1121136834.htm

Seems like an experimental attempt to create a "Moon Surface Micro Ecosystem". Not sure how legit it is though.

According to this article, they try to build a mini biosphere: https://www.telegraph.co.uk/news/2018/04/13/china-plans-grow...

Huh, interesting. I'm left wondering whether China has a Planetary Protection Officer, though of course the Moon is barren so it doesn't really matter…

Throw enough bullshit at a problem and something is bound to grow...

It isn't just barren. It's sterilized of any Earth life that may have happened along every month, which gets up to 250 degrees F (~120 C), and even if something survives that, there's never a window of time in which something like livable conditions obtain, because once out of the sterilizing sunlight the temperature immediately heads for a decent approximation of the average temperature of the cosmos. (Doesn't seem to quite get there, but it's cold enough that you could pour liquid nitrogen on to the ground and it would stay liquid if you held it at 1atm pressure. Dunno about vacuum.) So between the extreme thermal cycling and hard radiation, even Earth's best aren't going to get a foothold up there.

This is in contrast to places with a non-trivial atmosphere or standing liquids, which may moderate the environment enough that something could conceivably live. Something could conceivably live on Mars, something that isn't even necessarily that far from some things that live on Earth. Nothing will live on the Moon. You can fling as many gallons of the scummiest pond water you can find from any pond water on Earth on the moon, and you're not going to "contaminate" it with life.

I'm sure tardigrades have fared worse and survived, at least for a little while.

We really, really need more data on the responses of living creates to 1/8g. We've got all the 1g data. We've got a considerable amount of 0g data from ISS experiments. But we just don't know how living creatures respond to lunar or martian gravity. And knowing that will be very important for future colonization efforts.

Couldn’t we get that from a spinning satellite closer to earth?

No, the satellites stay in orbit only because the net G they experience is 0.

I believe the parent was referring to pseudogravity via rotation ('centrifugal force')-- hence the reference to a spinning satellite.

And how this related to the proximity to the Earth? I think the OP meant being close to the Earth would result in a gravity due to the proximity.

I read it as being cheaper to get experiments there (1kg to LEO is cheaper than 1kg to soft land on the moon)

If that's the correct meaning, then O.K. My bad.

Yes, exactly what I meant. It seems a lot easier to get an experiment into orbit than onto the moon. If you connect two halves of the satellite with a long tether, you could reduce the coriolis effects, if that's really an issue.

There are spinning experiments on the ISS.

Spin can indeed create (effective) gravity, but it differs due to the coriolis effect. We'd have two options: We can build a really big satellite, so as to minimize that effect -- or we could assume plants aren't sensitive to it, and hope for the best.

Needless to say, most scientists aren't fans of the second option.

Incidentally, long-term it would be possible to achieve 1g on the moon by way of a similarly huge centrifuge.

Another option is simply using a tether and a counterweight.

I can't grasp the centrifuge option, won't there still be two forces? It'll be more like those carnival rides than artificial gravity. A dropped ball won't fall straight "down".

On Moon?

The compartments would have to be tilted relative to the centrifuge, such that down becomes properly down.

I assume it's to provide food for the cane toads.

https://www.theonion.com/moon-now-overrun-with-cane-toads-af...

Don't know this time, but Chinese textbooks mentioned the radioactive space environment could cause mutations in the genes, creat new varieties.

Is this something they are trying to study, or trying to protect against?

You can do it more cheaply using a radioactive source on Earth. https://en.wikipedia.org/wiki/Mutation_breeding

Nice: giant worms in a world with scarce water laying in caves.

Let me know when I can buy a stillsuit and then we'll talk.

Teoretically you learn to build it yourself....

I have ridden the mighty moonworm!

There are already hard at work planning for a clothing factory.

It's traditionalist/nationalist symbolism of claiming the greatness, much like Russians hanging up Orthodox icons on ISS.

"hanging up"

How can you "hang" something in microgravity

https://www.wired.co.uk/article/international-space-station-...

https://i.imgur.com/uEnk8gj.jpg

Easier than in full gravity, I imagine.

Velcro, I imagine.

Duct tape.

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