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Knowledge_Seeker
2006-Sep-03, 03:56 AM
I've heard about this, but what is the dark side of the moon?

From what I am led to belive, this dark side, is a half of the moon that we can't see. We have not seen it, and when the moon spins although some of the moon may be lit up with light, this dark side will remain dark.

If this is true then how is this possible?

Ken G
2006-Sep-03, 04:04 AM
It isn't possible. The "dark side" is a misnomer, it's no darker than the side toward us. It's just the side we never see, not because it's dark, but because the Moon is always in the way. This is also why the Moon that we do see always looks the same (the so-called "man in the moon"). Look up "lunation" on the astronomy picture of the day to get a very good look at this. All your confusion stems from the simple poor choice of the word "dark" in that expression.

Van Rijn
2006-Sep-03, 04:11 AM
I've heard about this, but what is the dark side of the moon?


It's the side that isn't getting sunlight, lunar night. We often see the dark side of the moon.



From what I am led to belive, this dark side, is a half of the moon that we can't see. We have not seen it, and when the moon spins although some of the moon may be lit up with light, this dark side will remain dark.

If this is true then how is this possible?

The side of the moon we can't see from earth is properly called the "far side" of the moon (http://en.wikipedia.org/wiki/Far_side_(Moon)). Although it is a commonly misused term, it is incorrect to call it the dark side of the moon.

hhEb09'1
2006-Sep-03, 04:11 AM
There are also other meanings for the word "dark"--one of them is "concealed or secret" (as in "the dark side of the moon" or "darkest Africa"), but similar shades of meaning are "lacking enlightment" (as in "The Dark Ages") or "exhibiting evil characteristics" (as in "dark magic"). I don't think anybody really says "dark side of the moon" anymore, except Pink Floyd fans :)

astromark
2006-Sep-03, 04:21 AM
Near to first quarter and through the last quarter phase we see only half of the side of the moon that is Earth facing. When we see a full moon the side of the moon we are looking at is facing the sun and, thus lit. At this time only could you say that the far side of the moon is dark. The moon rotates on its Axis once every 28 days which is also the time it takes to complete 1 revolution of Earth. We only ever see one side of the moon. Likewise the inhabitants of the far side of the moon would have know knowledge of planet Earth. They would never have seen it. Unless they go walkabout.

astromark
2006-Sep-03, 04:24 AM
A signifacant recording of 'Pink Floyd's' music.

WaxRubiks
2006-Sep-03, 04:42 AM
there is the dark side, there is the light side and then there is.....The Twilight Zone..............

Celeste
2006-Sep-03, 03:07 PM
There are also other meanings for the word "dark"--one of them is "concealed or secret" (as in "the dark side of the moon" or "darkest Africa"), but similar shades of meaning are "lacking enlightment" (as in "The Dark Ages") or "exhibiting evil characteristics" (as in "dark magic"). I don't think anybody really says "dark side of the moon" anymore, except Pink Floyd fans :)

I buy that one.

Just as "bald" eagle means not "featherless", just "white headed".

Another common misnomer relating to the moon is "crescent". Widely used in English for "quarter", or close to quarter. But in fact, crescent comes from the French "croissant", which means "growing", aka "waxing".

So a "waning crescent" is a paradox.

Ken G
2006-Sep-03, 05:50 PM
Tiny nitpick-- crescent means close to new, not close to quarter. But your point is well taken. Even the French have the same problem when they eat bread shaped like a "croissant"-- how do they know that Moon was waxing? At some point, the origin of word no longer controls its meaning-- the meaning transcends its humble beginnings.

Tobin Dax
2006-Sep-03, 05:52 PM
I buy that one.

Just as "bald" eagle means not "featherless", just "white headed".

Another common misnomer relating to the moon is "crescent". Widely used in English for "quarter", or close to quarter. But in fact, crescent comes from the French "croissant", which means "growing", aka "waxing".

So a "waning crescent" is a paradox.
1) A "crescent," in English, is a shape like that of a croissant roll.
2) Crescent phases of the moon are between new and quarter phases, as the lit part of the moon is similar to that shape.
There is no misnomer.

hhEb09'1
2006-Sep-03, 06:41 PM
Tiny nitpick-- crescent means close to new, not close to quarter. dictionary.com (http://dictionary.reference.com/search?q=crescent) lists something different: "3a. the figure of the moon in its first or last quarter, resembling a segment of a ring tapering to points at the ends." My Ame.Her.Dic. says "1. The figure of the moon as it appears in its first or last quarter, with concave and convex edges terminating in points."


There is no misnomer.He did say it was widely used in English.

I think he was just pointing out the conflict with the entymology (http://www.bautforum.com/showthread.php?p=33556#post33556).

Ken G
2006-Sep-03, 06:49 PM
dictionary.com (http://dictionary.reference.com/search?q=crescent) lists something different: "3a. the figure of the moon in its first or last quarter, resembling a segment of a ring tapering to points at the ends." My Ame.Her.Dic. says "1. The figure of the moon as it appears in its first or last quarter, with concave and convex edges terminating in points."
(bold added)
No, that's not different from what I said. If it is in the first or last quarter, then it is close to new, in the sense that new is the centerpoint of the period described. But if it is close to the quarter, then it needn't be in the first or last quarter, it could certainly be gibbous and be near to a quarter phase. You are incorrectly nitpicking my nitpick!

Knowledge_Seeker
2006-Sep-03, 06:56 PM
so basically the reason why we cannot see the other side of the moon is that the moon takes 28 days to spin on its axis and it takes 28 days to make a revolution around the earth, thus we only see one side.

it also seems like i may have misworded my question. the word dark is being stresssed too much. i guess what i meant was why can't we see the other side of the moon? i used the "dark side" of the moon as a reference to what is more popularly known.

grant hutchison
2006-Sep-03, 07:05 PM
In English, the first usage of "crescent" (up to around 1600) was to indicate the waxing moon, anywhere from new to full. The waning moon was "decrescent". Luna crescens and luna decrescens, in Latin.
Somewhere in the late 1500s, though, someone rehooked the meaning to the shape we now call a "crescent".
I'd guess the French must have gone through a similar evolution: it would be fascinating to explore how both languages ended up making the same switch.

Grant Hutchison

hhEb09'1
2006-Sep-03, 07:23 PM
You are incorrectly nitpicking my nitpick!Ah! :)

[begin corrected nitpick mode]

Tiny nitpick-- crescent means close to new, not close to quarter.You can't get closer to new than new in an eclipse, but clearly that is not a crescent :)
[end mode]

astromark
2006-Sep-03, 07:46 PM
waxing, crescent, croissant, gibbous, full, new, and, bother its cloudy again. who mentioned croissants,? As I struggle yet again with this language.

Gillianren
2006-Sep-03, 07:51 PM
So a "waning crescent" is a paradox.

No, it's an oxymoron.

Lord Jubjub
2006-Sep-03, 07:57 PM
As to the OP, I think your original intended question has been answered.

Though I understand there is a slight bit of wavering in the moon's orbit such that we can occasionally see a sliver of the "far side" of the moon.

mattyh
2006-Sep-03, 09:00 PM
A signifacant recording of 'Pink Floyd's' music.


True!!! i'm 25 and it's probably my fav album of all time!!! 'time' is simply amazing!!!

Ken G
2006-Sep-03, 09:31 PM
Sadly, that song is not only amazing, it's true.

PhantomWolf
2006-Sep-04, 11:19 AM
It's the side the Sith live on, where as the Light Side is where the Jedi live. ;)

ZaphodBeeblebrox
2006-Sep-04, 11:04 PM
As to the OP, I think your original intended question has been answered.

Though I understand there is a slight bit of wavering in the moon's orbit such that we can occasionally see a sliver of the "far side" of the moon.
It's Called LIBRATION ...

Essentially What Happens, Is The Moon Orbits In The Shape of an Ellipse ...

The Result Is This (http://apod.nasa.gov/apod/ap010218.html) (Note, Do Not Look Directly at it)!