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Name:  Dylan
Status: student
Grade: 6-8
Location: IN
Country: N/A
Date: 4/29/2005


Question:
If there is no light, can an object still have color?


Replies:
The object's color can only be observed with light. If you have a red ball, and turn out the room lights, there is no way to know the ball is red. Of course when you turn back on the lights, the ball has not changed to yellow, it is still red. But in the dark, you cannot tell. So maybe the simple answer to your question is "no".

Steve Ross


No ... color in the case you posit is a manifestation of the interaction between electromagnetic radiation and a material object that absorbs and reflects certain wavelengths...then the detectors (our eyes) receive the certain wavelengths to which we ascribe certain descriptions...called colors...that exist whether we are there to detect of them or not.

Peter Faletra


Yes, that colour is black, but the object would not be seen. This would only occur in cases like 'the blackness of space' etc.

Howard Barnes


IF we look at a flower and see it as red, it is because that flower is absorbing all the colors of light except for red. The red light is being reflecting, or bouncing off of the flower. So, we see what is reflected. Everything has certain chemical make-up that makes something reflect some light and not other light. So, if that same flower we talked about earlier is in the dark, it still has those certain chemicals that make it reflect red, but you cannot tell because you cannot see the refection. I guess you could say that light gives color to an object, without light, there is no color.

Grace Fields


Each object carries within itself some memory of what colors it would reflect, if white light were suddenly shined upon it. So yes, I generally think of things in the dark as having intrinsic colors.

Of course, if there were no light in the whole cosmos, that might change things...

Jim Swenson


It is important to realize that, we can only see an object if light from that object reaches our eyes. That sounds obvious, but it makes an important point: the way an object appears depends on our perception of it. Without light, it does not even make sense to describe how something looks. If you look at a "red" object, it appears red because red light from the object reaches our eyes. That light may have been reflected off the object or transmitted through the object or it may have been created (emitted) by the object itself. But whatever the source of light, we can only perceive the color red if red light hits our eyes. Let us say the object is a book with a red cover (so it does not emit light). Put that book in a completely dark room and it will not appear red. In fact, it will not appear at all. Its molecular structure has not changed a bit, but at that moment, it makes no sense to describe the object as "red".

So the short answer to your question is, "No, there is no such thing as color in the absence of light." When we say that an object is red, it would be more accurate to say that we perceive the object as red.

Christopher Perkins


his question is, of course, a cunning version of "If a tree falls in the forest, and no one is around, is there a sound?" Color is the perception most affected by light's wavelength; hence, no light, no color.

Mike Loop


Without light there is no color. Even more specifically, without VISIBLE light (wavelengths between about 400 to 700 nanometers) there is no color. Exceptions are possible in special cases where electronic devices detect electromagnetic radiation outside this range into radiation within this range. But in the usual sense-- no light, no color.

Vince Calder


We could view this question as a philosophical question rather than a scientific one. But let us do the scientific approach.

One of the principles of science is that no statement can be made unless it is first observed or measured. Since color is the result of the interaction of matter with light, then removing light, removes the interaction, and therefore removes the possibility of any kind of measurement or observation.

Another important principle in science is that once a property has already been measured or observed, even if it is no longer observed, and unless something is observed to change the property that was measured, then it can be assumed that the property remains constant. Thus, having observed that grass is green, I no longer need to keep observing it to assume that it is still green. Thus, at this point, I no longer need light to know that grass will be green if I observe it again (using light).

Roberto Gregarious


Dear Dylan,

You need light to be reflected off an object to see it. White light is made of all the colors in the rainbow. When we see light from the sun or a light bulb, all the colors are in there. We can see them with a prism or when there is water in the air after a rainstorm. We see the rainbow of colors. We see all different colors when light from the sun or a bulb is shining on it. This is called white light. If would you shine a pure blue light on a pure red object it will appear black because there is no red light in the light you are shining on it. So no red color can reflect to your eye. You would not see a red object, just a dark one.

How colors look depends upon the kind of light they are in. Sometimes we look a little different in the bathroom light than we do outside. It all depends upon the kind of colors that make up the light.

I hope this makes sense. You can always write back if you want me to try a better explanation.

Martha Croll


Hi Dylan,

This reminded me of the saying... "If a tree falls in the forest, and there is no one around to hear it, does it make any noise?" I think that most of us would agree that it would because we understand that our world is governed by certain physical laws and these laws continue even when we are not around to perceive their manifestations.

Each object has the ability to absorb light of certain wavelengths within the visible spectrum and it is the reflected wavelengths that our eyes see and our brains perceive as color. With no light, our eyes are unable to do their job, but the object in question still has the ability to absorb light. By my way of thinking, the object still has color, we just cannot see it if there is no light.

Bob Hartwell



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