On a hot day, if you look at the road, on the horizon there appears to be a lake, or water. If there is an object behind the "lake", such as a telephone pole, it is reflected in the mirage. If the water really isn't there, then how can there be a reflection in it?
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A mirage, derived from the Latin mirari, meaning 'to be astonished', is an optical phenomenon which often occurs naturally. The kind most commonly seen (known as inferior mirage, because the inverted image lies below the upright one) is produced by the refraction of light when it passes into a layer of warm air lying close to a heated ground surface (see highway mirage). This is an example of gradient index optics.\n\nFor more info:\nhttp://en.wikipedia.org/wiki/Mirage
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I don't believe in ghosts, but I do know what I saw wasn't human. Me and a friend were driving on the highway when suddenly a large 10 ft white object floated over the median and into my lane. I swerved to avoid it and got a weird feeling about it. I thought maybe it was a trash bag or some tarp or something, but it looked smokey.. almost like fog, but yet it was in a defined form that looked like a being. I asked my friend if it was a trash bag, and he said no it definitely was not. I saw what was that? And we both had a period of silence. We both decided that it had to of been a ghost. This was out in the middle of nowhere, I belive near some battlegrounds. I've also had another experience with the same friend. We were both working on our computers when suddenly there was a loud CLAP to the left of us. It sounded like someone clapped right next to my ear. Inquiring what it was, we never decided on anything logical. I tried to calm myself saying maybe it was something electrical, or mechanical, but there was no logical explanation to be found. Very very strange.
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As there is no source of light in the sky apart from the Sun, then everything we see is reflected light. ; Thus the sky can only look black if all reflective matter is removed.
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wow, what a cool way of thinking!  I have wondered sometimes that when I walk up to a mirror and then walk away, where does my mirrior image go?  Does it go do something else until I summon it to the mirror again?
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http://www.grand-illusions.com/moon.htm\n\nThe Moon Illusion\n\nThe moon illusion is one of the most famous of all illusions. Stated simply, the full moon, when just above the horizon, appears much larger than when it is overhead. Yet the moon, a quarter of a million miles away from the earth, always subtends the same angle wherever it is in the sky, roughly 0.5 degrees.\n\nThe first problem is for photographers. A wonderful picture presents itself, with the full moon just rising above a spectacular horizon. Click, the picture is taken. Yet the result is disappointing. The moon seems much smaller in the photograph than it did when viewed with the naked eye. Even professional photographers fall for this one. Yet on a normal lens, 50mm on a 35mm camera, the field of view is around 50 degrees, and the width of the moon, subtending an angle of 0.5 degrees, will be 100th of the width of the photo! Many photographs that you see in magazines, containing both a moon and a landscape, will be composites. The landscape will be taken with a normal lens, the moon taken with a telephoto lens, to get a bigger image.\n\nHow does this illusion come about? Since the moon always subtends an angle of 0.5 degrees, the image on the retina must always be the same. Clearly the problem is one of interpretation. One simple experiment shows this to be so. A full moon just above the horizon will not appear so large to the human eye if a piece of paper is held up to that eye with a hole in it, so that only the moon can be seen through the hole and not the horizon. If the other eye is open at the same time, viewing both the moon and the horizon, the two eyes will each see different sized moons!\n\nThe explanation is believed to be as follows. We 'know' that a cloud that is overhead will be larger than when it moves towards the horizon. And an airplane that is a mere speck on the horizon becomes large when it is overhead. And we are all familiar with standing under a tree which seems enormous, yet at a couple of hundred paces seems insignificant. It would seem that so much of our world is interpreted this way that we are ill-equipped to cope with an object like the moon, that subtends the same angle at the eye, whatever position it occupies in the sky. And so our brain 'interprets' the image that it 'sees', and tells us that the moon is larger than it really is.\n\nHendrik Ball\n\n\n\nFrom: http://www.straightdope.com/classics/a2_110.html\n\n\nDear Cecil:\n\nI have noticed that the moon (and the sun, for that matter) appears very large just as it rises and sets. When it is overhead, it seems tiny by comparison. The color is also vastly different, but this can be easily explained by the fact that we view the moon through varying ''thicknesses'' of atmosphere as it makes its way across the sky. But this explanation seems insufficient to account for the change in size. So what's the straight dope? --Frank M., Los Angeles\n\nCecil replies:\n\nBelieve it or not, Frank, they've been arguing about this for two thousand years, and it's about time I got things straightened out. First of all, let me make it clear that the effect is an optical illusion. If you measure the moon with a ruler held at arm's length (a paper clip bent into the shape of a calipers will also work), you'll find it's always the same size no matter where it happens to be in the sky. If anything, the moon is slightly smaller at the horizon than it is at the zenith, mainly because it's 4,000 miles (the radius of the earth) farther away. (If you don't understand why this is so, draw yourself a picture.) Nonetheless, most people are convinced that, area-wise, the moon's at least twice as big when it's near the horizon as when it's overhead.\n\nNumerous theories have been advanced to explain the ""moon illusion.'' At one point people thought it had something to do with the angle at which you hold you
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Ah a question right up my alley...Moon - no you cant see the mirror, it would take 6 seconds for a light beam to get from here to there and back. Look for the crater Tycho (most notible because of the "ray" pattern) it is in the NE corner of the moon (you will see it in the SW corner because telescopes invert the image. Several other craters and mountains, make note of shadow positions. Using a lunar chart, find the Sea of Tranquility (Mare Tranquillium) where we first set down in 1969.\n\nSun - Using a white card held up to the eyepiece (some scopes have a bracket that can do this) Line the scope up so that it points to the sun DO NOT LOOK THRU THE SCOPE USE THE SHADOW ON THE GROUND. Focus the suns image on the white card and follow sunspots.\n\nOther planets Mars - track mars throughout the year and note the stars behind it.  As you see in just a few months mars will appear to go backwards in the sky then go forward again,  This is called retrograde.\n\nYou know of jupiter and saturn ring tilt, great spot moons etc.\n\nStar clouds and star clusters - you will need a star chart and not all are visable at the same time - M42 Orion Nebulae in his belt, M31 Andromada galaxy, the only object outside our galaxy visable to the naked eye located just above the second of third pair of stars coming off the great square pegasus - in the big dipper, second star in the handle should see a double star, this was used to test ship navigators in olden times, they had to be able to see the two stars with the naked eye.\n\nThat should keep you busy for one night LOL just kidding...email me anytime you need help
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Is the mirror flat? or it is a curved one? and position is relative to what? Position is always relative to each other. So:\nIf it is flat and relative to the mirror, the reflection is as far as our distance to the mirror.\n\nIf it is flat and relative to us, the reflection is twice as far as ourselves from the mirror OR as far as our distance to the mirrors itself, depending on the context.\n\nIf it is curved, it depends on the formula 1/f = 1/do + 1/di
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In geometrical optics with a pointlike sun the airplane would cast a shodow on the surface.\n\nBut: 1) The sun isn't pointlike but appears as a disc in the sky, so if light from diffent edges of the disc would cross under the plane ther would be no sharp shadow anymore, from a viewpoint on the surface the plane wouldn't cover the sun as whole\n\n2) Light is a wave, so geometic optics is not the whole story, there is refraction that bends the light into the shadow region. That's what you call "refill the void".
202044
the sun was behind the clouds, therefore there was a shadow.
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you can try total internal reflection of light using a keychain laser (commonly availble) and tub filled with water. all you have to do is put a small piece of mirror in the tub filled with water, let laser fall upon it. see the trajectory of the reflected beam ofr different orintations/angle of reflections and you will find that for certain critical angle the reflected beam is trapped in the water due to the internal reflection of the laser. you can do the same thing by choosing a transparent bottle with a small hole on the curved surface close to the base. now fill it with water, and see that water flows out of the hole in a parabolic fashion, now shine the laser from the opposite side to illuminate the water column. take a white plastic sheet allow the water to fall upon it, you will find that the water emmits light. this also explains how fibre optics work.
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Side view could be profile; strip of land is isthmus (strait is actually water)
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A mirage is a naturally occurring optical phenomenon. The kind most commonly seen (inferior mirage - where the inverted image lies below the upright one) is produced by the refraction of light when it passes into a layer of warm air lying close to a heated ground surface. In deserts, mirages may give the appearance of a lake or other large body of water in the distance; as the previous writer stated, this is actually an image of the sky being refracted back up from the warm air lying over the sand.
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It is presumed that we perceive the sun/moon larger near the horizon because its in close proximity to buildings and other frames of reference, and our eyes compare the size of the moon to the buildings and other horizon features. \n\nUp in the sky, there is no frame of reference, and without it, the moon appears smaller.
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Well if you are talkin about a mirror made of floated glass a layman can c the quality of it other wise ind. know how is required i think (i am not proffesional in it, just being in a float glass plant for a week). If it is a mirror and you c a distracted reflection then b sure that there is impurity in the glass, as well as the transparency of float glass is supposed to be very high compares to the conventional one.
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The previous two answers are correct.  The surface of a still body of water is one of few naturally occuring situations producing a clear reflection.  Gravity, molecular motion, the freedom of molecules in a liquid to move to positions of lowest energy, and an index of refraction that differs from air all contribute.  Mercury is much better, since its reflectance is nearly 100%.  The surface of a pool of mercury is a nearly perfect mirror.
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there is an optical effect like this ( it is just a refraction at an interface - like water and air ) and sorry i can't remember either ( i will search tho )\n\ncool i searched the term ATMOSPHERIC REFRACTION and guess what LOL( go to Wikipedia )
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Umm I dont think this has anything to do with snell or refractions.\n\nLet me ask you this question: How come you can see a shadow on  the ground , but not in the air between the object and the ground?\n\nThe answer is that you can see shadows clearly on opaque surfaces like the ground or muddy waters, works resonably well on a translucent surface too. And does not work on a transparent surface like air or clear water.\n\nDo I hear you still asking WHY?\n\nA shadow is created when there is considerably lesser amount of light falling in a certain region. And you can notice a shadow when the amount of light reflected for a certain region of a surface is lesser. now a transparent surface does not reflect much light in the first place ( it lets it pass through, thats why the surface is transparent ). So you do not detect the disparity in the amount of light reflected back to your eyes, and u do not sense the shadow. now if there was an opaque surface behind the transparent surface, you will see a shadow on that.