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Do we need/want a 3-vote closure?
There's a recent discussion in the main meta Testing three-vote close and reopen on 13 network sites.
So I am wondering, as a few posts have 2,3, or even 4 close votes that haven't been closed/resolved, should we request for 3-vote close and reopens change to applied to our site as well?

My personal opinion is no. I think that would create a lot of back and forth. In cases where you think it's obvious a question needs to be closed or reopened, you can always flag for moderator intervention if it's having trouble getting enough attention.

"So I am wondering, as a few posts have 2,3, or even 4 close votes that haven't been closed/resolved..." meta questions always benefit from and garner credibility from specific examples. Can you add links to these recent examples of this issue? If there aren't any, then perhaps there isn't any issue.

There's an idiom that says: "Third time lucky" or "Third time is the charm". But I don't think it works here.

No, this controversial proposal to "close early, close often" is probably meant to apply to fast-paced sites where there isn't enough time to consider the merits of each question carefully, have a dialogue with the OP and see improvement's can't be made efficiently without all the question-closing drama and trauma1.
When there is no substantial danger posed by the possibility of a less-than-ideal answer begin posted, then the 2, 3, 4 close votes eventually decaying back to zero is a good thing. It shows there weren't a full 5 people who felt strongly enough about answer-prevention that an answer-blocking hold should be placed.
Low question-rate sites with good, healthy communities can do nicely with the standard SE features, no need to add something exotic or experiment on our new users.
If it ain't broke, don't fix it.

1New users and especially when asking their first question can easily be turned of by getting their question quickly closed and any answers blocked. So for this low question-rate fairly sleepy site that certainly doesn't have an overabundance of new users joining per week, I think we should avoid an fast-paced-site solution.

Agreed! I don't think our site has a problem with getting 5 close votes for questions that clearly need to be closed. Recent example: https://astronomy.stackexchange.com/questions/43651/is-there-any-cybersecurity-in-spacecraft-communication.  Our moderators also have no problem unilaterally closing questions, and we don't have an undo burden on moderators for closure (which are reasons sited in the referenced meta post for lowering the vote count).

I fully agree with "If it ain't broke, dont't fix it" - I never felt that this was an issue. I actually enjoy that questions are not closed with light-speed.


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Nuclear physics, relativity theory and quantum mechanic on Astronomy SE
Are questions about nuclear physics, relativity theory and quantum mechanics on topic?
I'm asking this because I'm trying to send a question about relativity theory on SE. But I don't know where can I send this - on Astronomy SE or on Physics SE?
Thanks for all the answers!

I think generally those would be better on Physics SE. Some relativity questions may be welcome here, but nuclear physics and quantum mechanics (except as they relate to cosmic principles such as stellar fusion and black holes) are pretty firmly Physics SE territory.

If you had a specific question or line of questioning in mind, you can edit your meta question above to highlight that and I think we could get you a more definitive answer.

@called2voyage No, I haven't got a specific problem or question.

I think physics would be better

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Should this question be reformulated or should I post a new question?
It seems there are many approaches to calculate the speed of Sun (for instance: Oort constant, CMBR, and others). Instead of having a "correct answer", what about "survey answers"? Should I change the question (edit / reformulate), or should I answer my own question and post another one? The only answer until now would not be disturbed, I think. In Astronomy SE are there survey questions? For instance: "Do you know another approach (for calculating the speed of Sun)?"
How was the speed of the Sun around the Milky Way Galaxy calculated?

Your question is not "what is the speed of the Sun?". It asks for the "speed of the Sun around the Milky Way galaxy", which is a specific question and should not be changed now there are answers to that question.
The "Oort constant" method isn't a different method, since the Oort constants have to be determined. The "CMBR method" doesn't tell you about motion with respect to the Galactic centre and would be an incorrect answer.
There are correct answers to this question but you haven't got one yet (though one is pointed out in comments).

I ask Astronomy SE moderators to revert/edit/reformulate the question. Thanks.

Oh, this is an interesting meta question!
Generally we are very careful not to change a question once an answer is posted, but I agree that what you are proposing doesn't really detract from or negatively affect the answer, other than preventing it from becoming "the" (accepted) answer.
Generally list questions1 are discouraged in Stack Exchange; questions requiring a long list of things as answers, as the answering can become unwieldly.
However there are plenty of well received exceptions to this, and it turns out that SE encourages questions that have many answer posts; multiple answers per question is even used as a basis for site graduation!.
So in this particular case for this particular question and topic I personally feel it will be fine to adjust your question to something like

What are the different approaches that can be used to determinee/estimate/calculate X?

or similar. You can leave a note under the current answer letting the author know of the adjustment (they don't get a notification) and explain that you appreciate their answer and it made you realize xyz and so have adjusted the question.

1For more background and discussion and thinking about "list questions" in the main SE meta:

What is the definition of a list question?
Are there "good" list questions as opposed to "bad" list questions?
Are list questions off topic?
The halting problem - or - the fallacy of "real questions have answers" not for the faint of heart :-)

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Thought experiment questions that aren't completely scientific?
Should one ask questions regarding some thought experiments on the Astronomy Stack Exchange? (Assuming that these thought experiments are somewhat related to astronomy/astrophysics but aren't completely scientific) ?

Astronomy is more of a hard science stack, so thought experiments are going to be, at best, right on the border of being off-topic. And it would probably need to be more than just somewhat related to astronomy/astrophysics. There are other SE sites, such as Physics and World Building. If it's more of a general physics question than it is an astronomy question, it would probably get a better answer there than here. World Building might be a good place to ask your more "out there" thought experiments.

From the help center under What questions are off topic here:

Questions that are purely hypothetical, for example a question such as 'Could a black hole destroy the universe' or 'What if our solar
  system had two suns' (however, feel free to visit World Building)

I think thought experiments fit this disqualification rather neatly, and I don't really see any reason to change it. Information found here should always come from a scientific perspective. If the question is not based in science or science is not applicable to the answer then there are better sites to use. In addition to the sites Donald listed, I would also suggest considering Science Fiction and Fantasy (as per the SF question we had today).
If you think such a thought experiment wouldn't fit the above disqualification, it may be helpful to provide an example of what kind of thought experiments you are thinking of.

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