Question about Phases of the Moon. Thanks

AI Thread Summary
The discussion centers on understanding how to shade the Moon's surface as viewed from space, specifically from a perspective above the North Pole. It clarifies that only half of the Moon is illuminated at any time, the side facing the Sun, regardless of the lunar phase observed from Earth. Participants debate the correct shading for positions A-E, emphasizing that shading should represent the illuminated side, not the phases like waxing or waning as seen from Earth. The consensus is that the correct representation for a waxing crescent would show the illuminated sliver on the right side when viewed from space. Ultimately, the correct shading technique is confirmed, highlighting the importance of viewing the Moon's illumination from the proper perspective.
nukeman
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Ok, here is the problem I have:

Figure 2 shows the Moon in its orbit about the Earth, as viewed from space high above the
North Pole. Copy the figure into your lab book and for each position A − E shade the appropriate
portion of the Moon’s surface as viewed from space, NOT as viewed from Earth.

here is the image:
http://i51.tinypic.com/2coo1lz.jpg

Here is my attempt:
1hwmq8.jpg



Am I correct?
 
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Doesn't look right. Is shaded supposed to mean illuminated or dark?

Only half of the moon's surface is illuminated at any given time -- the half that faces towards the sun.
 
Then I am doing it wrong, I thought I would have to shade it based on moon phases like waxing cresent and what not.


Any maybe shade one of them, point me in the right direction?

Thanks!
 
You didn't answer my question. In your attempt, is shaded supposed to mean lit or dark?

As I said before, the side that faces towards the sun is lit (obviously). For example, at position D, the right half of the moon would be lit. The left half would be dark, because it faces away from the sun. Since the left half is the half that faces towards Earth, this position happens to correspond to a new moon phase.

EDIT: Well, new moon would be somewhere between D and E, when they're all completely aligned.
 
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Ahhhh. I see.

So, just so I make I got this right, let's take E

Its in Wax Cresent correct?

So, the small sliver of moon showing, would be on the right side ?
 
nukeman said:
Ahhhh. I see.

So, just so I make I got this right, let's take E

Its in Wax Cresent correct?

So, the small sliver of moon showing, would be on the right side ?

The question asks for the shading as seen from space, NOT as viewed from the Earth. What would the Moon look like looking down from a distance high above the North pole?
 
nukeman said:
Ahhhh. I see.

No, you don't.

cepheid said:
Only half of the moon's surface is illuminated at any given time -- the half that faces towards the sun.

cepheid said:
As I said before, the [half] that faces towards the sun is lit



nukeman said:
So, just so I make I got this right, let's take E

Its in Wax Cresent correct?

So, the small sliver of moon showing, would be on the right side ?

No! That is how it would appear from EARTH, but that's only because observers on Earth cannot see all of the illuminated side from their vantage point. That doesn't change the fact that there is always an illuminated side -- one entire half of the surface is always lit, which means that at every single one of the positions shown, you will have half of the surface shaded and half not shaded.
 
Right, so half moon is always lit.

So then, the following diagram is correct?

http://i55.tinypic.com/bj5t20.jpg

Note: the dotted part of the moon is the lit portion.
 
anyone? :)

nukeman said:
Right, so half moon is always lit.

So then, the following diagram is correct?

http://i55.tinypic.com/bj5t20.jpg

Note: the dotted part of the moon is the lit portion.
 
  • #10
nukeman said:
Right, so half moon is always lit.

So then, the following diagram is correct?

http://i55.tinypic.com/bj5t20.jpg

Note: the dotted part of the moon is the lit portion.

That is correct.
But, for future reference, the common notation is to shade in the... erm... shade. :)
 
  • #11
nukeman said:
Right, so half moon is always lit.

So then, the following diagram is correct?

http://i55.tinypic.com/bj5t20.jpg

Note: the dotted part of the moon is the lit portion.

Now, that is correct, which of the Moon positions A − E best corresponds to the lunar phase shown?
 
  • #12
Well, you can eliminate a, b, and c, because they are either mostly lit, or half lit, and this picture is clearly mostly dark.

So, it's between E and D. Which position would allow you to see a sliver of light on the left part of the moon?
 
  • #13
Archosaur said:
Well, you can eliminate a, b, and c, because they are either mostly lit, or half lit, and this picture is clearly mostly dark.

So, it's between E and D. Which position would allow you to see a sliver of light on the left part of the moon?

Is it wanning crescent?
 
  • #14
Yes.
 
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