Things you don't need to know...

[pibbuR]

Now i feel stupid.

pibbuR

 

[bkrueger]

Fixed stars
From Wikipedia, the free encyclopedia

This article may be confusing or unclear to readers. Please help clarify the article. There might be a discussion about this on the talk page. (August 2020) (Learn how and when to remove this template message)
Kepler, Johannes. Mysterium Cosmographicum, 1596. Kepler's heliocentric rendition of the cosmos, containing an outermost “sphaera stellar fixar,” or sphere of fixed stars.

The fixed stars (Latin: stellae fixae) compose the background of astronomical objects that appear not to move relative to one another in the night sky, unlike the foreground of Solar System objects, which appear to move. Generally, the fixed stars are taken to include all stars other than the Sun. Nebulae and other deep-sky objects may also be counted among the fixed stars.

Exact delimitation of the term is complicated by the fact that celestial objects are in fact not fixed with respect to one another. Nonetheless, extrasolar objects move so slowly in the sky that the change in their relative positions is nearly imperceptible on typical human timescales, except to careful examination, and so can be considered to be "fixed" for many purposes. Furthermore, distant stars and galaxies move even more slowly in the sky than comparatively closer ones.

People in many cultures have imagined that the stars form constellations, which are apparent pictures in the sky. In Ancient Greek astronomy, the fixed stars were believed to exist on a giant celestial sphere, or firmament, which revolves daily around the Earth.

Ah, because Wikipedia says so...
Edit: "This article may be confusing or unclear to readers."

 

[pibbuR]

So does the Cambridge Dictionary: "a star that is so far from the earth that it seems not to move in relation to other distant (= far away) stars as the earth moves through space"

And so does the memory of pibbuR when he thinks about it

 

[bkrueger]

Ok, i concede that fixed star is a deprecated historical term. So I should have asked. Which is the star nearest to earth...

 

[HiddenX]

So does the Cambridge Dictionary: "a star that is so far from the earth that it seems not to move in relation to other distant (= far away) stars as the earth moves through space"

And so does the memory of pibbuR when he thinks about it

So your answer would still be correct, if you are an alien living at a distant star - now I know why you speak so diffrent...

 

[pibbuR]

And why I fiercely claims that earth is not visited by aliens.

 

[bkrueger]

And why I fiercely claims that earth is not visited by aliens.

Do you feel alienated?

 

[HiddenX]

What is the perimeter?

 

[pibbuR]

If I try to answer that one I fear I will raise a QI klaxon alarm.

 

[bkrueger]

32

 

[HiddenX]

The exercise is from Cliff Pickover. I can recommend his Math book from 2009.

 

[bkrueger]

The exercise is from Cliff Pickover. I can recommend his Math book from 2009.

Thanks, looks like an interesting read...

 

[Redglyph]

Nice one!

There are a few interesting problems on this channel:

https://www.youtube.com/c/MindYourDecisions

The author also made a few books; I'm currently having some occasional fun with Mind your Puzzles but I'm not far enough to give a verdict. So far it's pretty good.

 

[Lakorus]

What is the perimeter?

Uhm, obviously the correct answer is 32. But how can it be calculated? The vertical lines are trivial - both sides add up to 8 each. But the horizontal ones?

 

[Redglyph]

Uhm, obviously the correct answer is 32. But how can it be calculated? The vertical lines are trivial - both sides add up to 8 each. But the horizontal ones?

Take the missing horizontal segment as unknown "x" and write down the sum of all segments, you'll see that x cancels itself out.

 

[Lakorus]

But there are two horizontal segments that are unknown?

 

[HiddenX]

But there are two horizontal segments that are unknown?

Here's the solution:

 

[Lakorus]

Well, that's actually pretty simple, once it is written down for dummies... I was still thinking that the correct way was to precisely calculate d+e as well.
Thanks

 

[Redglyph]

But there are two horizontal segments that are unknown?

I meant d - e. Or e, it's the same, you can deduce the rest from only one unknown.

 

[Corwin]

That was a fun little activity, keep them coming!!