The definition of Incidence Angle
you are using to debunk is so utterly
wrong and your debunk using the wrong definition so lengthy and seemingly confident that I just had to call you out in case people actually believed
this particular debunk.
Incidence angle your are referring is a common measurement found in aerial images of the Moon and other planetary bodies. This measurement is always
between 0° and 90° and defines the angle between surface normal (a line straight out towards the sky from surface the object is located) and Sun's
vertical position (a line straight to the sun from the object). If the Sun is directly above the object, the incidence angle will be 0°, if the sun
is directly on the horizon, the incidence angle will be 90°.
Angle of incidence does NOT tell the DIRECTION of shadow. Incidence angle determines the LENGTH of shadow. The higher the incidence angle, the longer
the shadow length will be. Imagine during the day when the Sun is high in the sky, shadow will be shorter (low angle of incidence) vs when during
evening when the Sun is low on the horizon and length of shadow will be longer (high angle of incidence).
Here is a simplified thought experiment to show why you CANNOT debunk anything by saying angle of incidence determines direction of shadow.
Assume that at noon, the sun is straight above your head (angle of incidence = 0°) and you cast no shadow.
Assume that at 10 AM, the sun is 60° above the eastern horizon. (angle of incidence = 30°)
Assume that at 2 PM, the sun is 60° above the western horizon (angle of incidence = 30°)
At 10 AM and 2 PM, the angle of incidence is same.
So, do you think your direction of shadow will be the same at 10 AM and once again at 2 PM?
According to Phage's debunk, the direction of your shadow will be same at 10 AM and 2 PM.
The correct answer is the LENGTH of your shadow will be the same, the direction will actually be roughly opposite depending on your latitude.
Basically, incidence angle is most commonly used to calculate the height of an object or depth of crater, by taking the length of shadow value and
incidence angle. Please check this post of mine to see
how incidence angle and length of shadow was used to calculate the height of a possibly artifical object on the Moon.
Originally posted by Phage
reply to post by wolveriine
Note the "incident angle" in the description of the image. That is the direction of the sunlight relative to the surface and the spacecraft. It is
80º. That is from the upper right of the unrotated image. It is not consistent with the "shadow".
If you look at the direction of the shadows in the craters you will see that the direction of the "shadow" of the "tower" does not match. Unless the
Sun was in a different location from the point of view of the tower and every thing else in the image, it is not a shadow.
The "shadow" is a feature (a crater perhaps) on the surface. The "tower" is a flaw in the photograph like many others.
edit on 2/10/2013 by Phage because: (no reason given)
edit on 11-2-2013 by PINGi14 because: (no reason