Thread: Moonlight

I looked on wiki and it stated that light is illuminated from the dust of the moon. If that's the case, why can't people see the light directed towards the moon at night? Stupid question or not!

It sort of is. The light reflected by the moon can be reflected because the moon is far enough away from the planet and angled properly. When the moon is seemingly not in the sky, the earth is in its way (this is how we have moon phases).

Originally Posted by Darius

It sort of is. The light reflected by the moon can be reflected because the moon is far enough away from the planet and angled properly. When the moon is seemingly not in the sky, the earth is in its way (this is how we have moon phases).

True, concerning the moon phases, but we can see the moon during daytime before sunset also. I don't think the moon emits light from the sun because we would see that light, night wouldn't exist. the light on the moon will travel in more than that one direction. I attached the link to wikipedia:

http://en.wikipedia.org/wiki/Moonlight

Ah, I see. Sorry, I generally don't look up things as simple as moonlight. It's really not that interesting.

You mean why does the night sky look dark and the moon bright if the moon is being illuminated by the sun?

Well, the light from the sun is all around the night sky, but without anything to reflect off of it's all going the wrong way to reflect back to our eyes.

Originally Posted by Numsgil

You mean why does the night sky look dark and the moon bright if the moon is being illuminated by the sun?

Well, the light from the sun is all around the night sky, but without anything to reflect off of it's all going the wrong way to reflect back to our eyes.

Numsgil, you made my question sound even better, but my question still isn't answered. This is deeper than I thought. Our eyes can see light even when we are in the dark, so why is the light directed towards the moon invisible?

Human eyes only see by reflection.

Originally Posted by sunlight7

Originally Posted by Numsgil

You mean why does the night sky look dark and the moon bright if the moon is being illuminated by the sun?

Well, the light from the sun is all around the night sky, but without anything to reflect off of it's all going the wrong way to reflect back to our eyes.

Numsgil, you made my question sound even better, but my question still isn't answered. This is deeper than I thought. Our eyes can see light even when we are in the dark, so why is the light directed towards the moon invisible?

Then I'm not sure I understand the question you were posing. The exact wording "why can't people see the light directed towards the moon at night?" can mean one of three things if not the first interpretation I gave. Please tell me if I'm getting warmer to understanding your question:

1. Why doesn't the Moon look like the Sun if it's reflecting back the sun's light. Or even more simply, why isn't the Moon and the sun the same color if the moon's light is reflected sunlight.

Answer: The moon absorbs the sunlight and then re-emits it in its own color. Much like how an apple looks red under white light.

2. If I point a flashlight at the Moon, why doesn't it illuminate the moon when the moon is all dark?

Answer: it would if it were strong enough.

3. Why do parts of the moon ever get dark at all?

Answer: Only half of the moon is ever illuminated by the sun. The ahlf that is facing the sun. The other half is dark. Much like how we have day and night on Earth. Because of the moon's orbit, most of the time we see the moon in "profile", where we can see part of the illuminated side, and part of the darker side (not to be confused with the dark side, which is the part that isn't visible from Earth).

If none of those three questions is what you're asking, the rephrase the question and let me try again.

Originally Posted by Darius

Human eyes only see by reflection.

Thanks for the replies all!

I think I found the answer, i'm doing research on the human eye now. Unless you have that info already darius?

Official sources would be best. Parroting is not my style.

Originally Posted by Darius

Official sources would be best. Parroting is not my style.

Well, your answer seems to be believable but I don't have proof.

...if you don't know that human eyes work entirely on reflection of light you must be blind. In which case how are you...

Doo doo doo doo doo doo doo doo.

Originally Posted by Numsgil

Originally Posted by sunlight7

Originally Posted by Numsgil

You mean why does the night sky look dark and the moon bright if the moon is being illuminated by the sun?

Well, the light from the sun is all around the night sky, but without anything to reflect off of it's all going the wrong way to reflect back to our eyes.

Numsgil, you made my question sound even better, but my question still isn't answered. This is deeper than I thought. Our eyes can see light even when we are in the dark, so why is the light directed towards the moon invisible?

Then I'm not sure I understand the question you were posing. The exact wording "why can't people see the light directed towards the moon at night?" can mean one of three things if not the first interpretation I gave. Please tell me if I'm getting warmer to understanding your question:

1. Why doesn't the Moon look like the Sun if it's reflecting back the sun's light. Or even more simply, why isn't the Moon and the sun the same color if the moon's light is reflected sunlight.

Answer: The moon absorbs the sunlight and then re-emits it in its own color. Much like how an apple looks red under white light.

2. If I point a flashlight at the Moon, why doesn't it illuminate the moon when the moon is all dark?

Answer: it would if it were strong enough.

3. Why do parts of the moon ever get dark at all?

Answer: Only half of the moon is ever illuminated by the sun. The ahlf that is facing the sun. The other half is dark. Much like how we have day and night on Earth. Because of the moon's orbit, most of the time we see the moon in "profile", where we can see part of the illuminated side, and part of the darker side (not to be confused with the dark side, which is the part that isn't visible from Earth).

If none of those three questions is what you're asking, the rephrase the question and let me try again.

None of those questions is what I am asking. I'm simply asking about the light directed toward the moon at night, why isn't it viewable to the human eye? If we can see the moon lit, shouldn't we see the light as in headlights from a car to an object?

That's what I thought you meant when I very first posted. The answer is that you can see headlights because they reflect off of stuff (trees, grass, drizzle in the air, etc.). There's nothing in space to reflect off of, so you don't see the light. Well, except where it illuminates the Moon and planets. Space is mostly nothing. Lots and lots of nothing. So all that light in the night sky from the sun isn't visible because it's heading the wrong way and there's nothing to turn it around.

Unless you mean the light that's directed at the Moon specifically. In which case, you can see that light. That's why you can see the Moon at all. It doesn't generate any light on its own.

I like that answer Numsgil and good job divining the question!

Sunlight7, sunlight is nothing special. It's just a lot stronger than the light from a lightbulb. Now, can you see the air illuminated between the bulb and a wall? Smokey room, maybe. Same for the moon.

It's always bothered me that looking at the moon I don't just know instantly where the sun is. Should be 100% intuitive, but I have to work it out in my mind. I think my senses of distance are way off.

Well, there is the Zodiacal Light. It is very faint and can only be seen with extraordinary conditions in areas with little light pollution. It is the sunlight reflected and scattered by the interplanetary dust inside the solar system plane. In order to see something, photons must reach the eye. Either directly from the source or by reflection or scattering.

Originally Posted by Darius

It sort of is. The light reflected by the moon can be reflected because the moon is far enough away from the planet and angled properly. When the moon is seemingly not in the sky, the earth is in its way (this is how we have moon phases).

What? How does the earth being in the way cause moon phases?

Originally Posted by Harold14370

Originally Posted by Darius

It sort of is. The light reflected by the moon can be reflected because the moon is far enough away from the planet and angled properly. When the moon is seemingly not in the sky, the earth is in its way (this is how we have moon phases).

What? How does the earth being in the way cause moon phases?

Just in case somebody has strange ideas about that:

Guess I can understand the moon phases but it looks to me as if the sun has rays that go in one direction unless reflected from an object as mentioned before. Then we have the axial tilt of the earth, so the suns rays are only visible unless an object (moon) is available to emit that light. Am I correct?

Originally Posted by sunlight7

Guess I can understand the moon phases but it looks to me as if the sun has rays that go in one direction unless reflected from an object as mentioned before. Then we have the axial tilt of the earth, so the suns rays are only visible unless an object (moon) is available to emit that light. Am I correct?

Yes. Well, during the day obviously you can see the sun in its full glory, but at night that's the case.

Yes indeed, you can see the sunlight straight from the sun, no reflection. Just don't stare directly at it and burn out your macula.

Originally Posted by Harold14370

Yes indeed, you can see the sunlight straight from the sun, no reflection..

Indeed. Indeed. I was puzzled, as I sat here looking at my laptop screen and occasionally glancing across at the flourescent and incandescent lamps, exactly how I was seeing them by reflection. (Which someone earlier in the thread apparently claimed.)