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Comment by hyperpallium | Hacker News Reader

Where's that? I couldn't fimd it in the linked article.

Sounds like Elon Musk's original idea for a greenhouse on Mars, to inspire via realtime cam. Is there any indication they'll have a public cam for it?

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It wasn't in TFA, but here's a source: https://www.bbc.com/news/science-environment-46724727

> The lander carries a 3kg (6.6lb) container with potato and arabidopsis plant seeds - as well as silkworm eggs - to perform biological studies. The "lunar mini biosphere" experiment was designed by 28 Chinese universities.

(Source for the silkworms, at least. I must confess that giant mutant moonworms are only conjecture... for now...)

Not entirely sure about all the ISS tests but most space biology experiments seem to be zero-g. We know a lot about how life survives at 1g and 0g but very little about in between, so hopefully it goes ok, quite a unique experiment.

ISS isn’t 0g, it’s actually about 0.89g. Even the moon is 0.166g. And that’s without getting super pedantic by saying there’s always some gravity anywhere you are in the universe.

ISS is in freefall though, which simulates 0G. Yes technically gravity is almost as strong as on the surface where ISS orbits, but there is no normal force opposing gravity.

Actually, the ISS isn’t in “freefall” either. Further, there definitely is a normal force (inertia) opposing gravity too, otherwise without that (and the occasional thruster burns needed due to drag from the atmosphere), it wouldn’t “continually fall and then miss the ground” as it’s normally described in layman terms.

There’s plenty of sources to back up what I said previously and here, but this provides a great description of why it’s wrong to say the ISS is in freefall:

https://www.quora.com/Is-ISS-considered-to-be-in-gravitation...

Hm, doesn't this violate the prime directive (or planetary protection guidelines)?

I think they'd have to dump something on the surface, but even if they did, who's going to enforce it? The moon's not Antarctica.

It absolutely does. You should file a complaint with the PDIPTF (Prime Directive Interplanetary Police Task Force) currently HQ in Ark 9, "My hole is bigger than yours", Holm 42, Level 686 on Makemake. In person. Be sure to ask for a complaints receipt.

The biggest reason for planetary protection guidelines is the risk of life escaping from the spacecraft and being mistaken for native life. The moon is so ridiculously inhospitable that it isn't much of a concern because no known life can survive without air or water, even before taking into account the extreme temperature swings. Somewhere like Mars or Europa has much more strict guidelines. Also, we sent people to the Moon, which are a lot messier than silkworm eggs.

Any bio nerds know why silkworms?

There's an obvious reference to Chinese culture in that one, curious what are the biological reasons to choose that creature over any other.

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