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  1. Subscriber FreakyKBH
    Acquired Taste...
    15 Jul '17 16:00
    At ~93M miles away, what is the degree of angle the sun's light would hit the earth?
  2. 15 Jul '17 16:35
    Originally posted by FreakyKBH
    At ~93M miles away, what is the degree of angle the sun's light would hit the earth?
    This is the science forum. Flat earth questions belong in 'spirituality'.
  3. Subscriber FreakyKBH
    Acquired Taste...
    15 Jul '17 19:19
    Originally posted by twhitehead
    This is the science forum. Flat earth questions belong in 'spirituality'.
    Science deals with what can be measured, observed, tested, repeated, falsified.
    The angle of the sun's light is such a phenomenon.
  4. 15 Jul '17 19:23
    Originally posted by FreakyKBH
    Science deals with what can be measured, observed, tested, repeated, falsified.
    The angle of the sun's light is such a phenomenon.
    The angle that light strikes the earths surface varies by location because the earth is a sphere. I assumed from your OP you were asking about an imaginary flat earth (and hence one that cannot be measured, observed, tested, repeated, falsified.)

    In short, your OP doesn't make any sense. You need to clarify what you are asking.
  5. Subscriber FreakyKBH
    Acquired Taste...
    15 Jul '17 21:04
    Originally posted by twhitehead
    The angle that light strikes the earths surface varies by location because the earth is a sphere. I assumed from your OP you were asking about an imaginary flat earth (and hence one that cannot be measured, observed, tested, repeated, falsified.)

    In short, your OP doesn't make any sense. You need to clarify what you are asking.
    I disagree.
    The angle could not be different, no matter where on the globe you are standing, simply because of the distance.
  6. 15 Jul '17 22:07
    Originally posted by FreakyKBH
    I disagree.
    The angle could not be different, no matter where on the globe you are standing, simply because of the distance.
    When you have figured out what you really want to ask, then post it. Right now you are not making any sense.
  7. 15 Jul '17 22:34
    Originally posted by FreakyKBH
    I disagree.
    The angle could not be different, no matter where on the globe you are standing, simply because of the distance.
    Then why is it (this globe) dark one side and simultaneously light on the other?
  8. Subscriber FreakyKBH
    Acquired Taste...
    15 Jul '17 23:27
    Originally posted by divegeester
    Then why is it (this globe) dark one side and simultaneously light on the other?
    The sun is still coming from the same angle.
  9. Subscriber FreakyKBH
    Acquired Taste...
    15 Jul '17 23:27
    Originally posted by twhitehead
    When you have figured out what you really want to ask, then post it. Right now you are not making any sense.
    The OP is the question which is put to anyone who has an idea on the topic.
    Given the distance of the source, at what angle will the light hit any object, namely, the earth?
  10. Standard member sonhouse
    Fast and Curious
    16 Jul '17 01:40 / 7 edits
    Originally posted by FreakyKBH
    The OP is the question which is put to anyone who has an idea on the topic.
    Given the distance of the source, at what angle will the light hit any object, namely, the earth?
    It is a spherical wavefront and you can calculate the difference between points that light hits at the exact same time, supposing the sun was putting out pulses a trillionth of a second apart and you could know exactly what pulse you are tracking then you can see the wavefront hits Earth at the closest distance and then hits the edge about 24,000 microseconds later.

    But the angle you can do pretty simply, Earth's orbit around the sun is about 550 million miles in circumference, close enough for government work. Earth is about 8000 miles wide so across Earth is a change in angle of about 1 part in roughly 68,000. (meaning you can put about 68000 Earths side by side in the circle of Earths orbit) 1 arc second is cutting a circle into 1,296,000 parts (360 degrees * 60 minutes * 60 seconds of arc) so divide that by 68000 and you get roughly a difference of about 18 arc seconds from one side of Earth to the other when you point a very accurate caliper at the sun measuring the angles. So from dead center of Earth, (the closest point on Earth to the sun, a line drawn from there to the closest point on the sun, (center line of Earth to the center line of Sol) the angle would be +/- about 9 arc seconds. This is a back of the envelope thing, I didn't look up exact numbers but these numbers are fairly close.

    But why is this of interest?

    My guess is you will tie this to the flat Earth somehow, perhaps saying see, the sun is say 3000 miles above Earth and subtends an angle of 18 arc seconds so it OBVIOUSLY 0.3 mile across. Something like that? Saying, see, you can't tell the difference if it is 93 million miles away V 3000 miles. Is that your point?
  11. 16 Jul '17 07:19
    Originally posted by FreakyKBH
    The OP is the question which is put to anyone who has an idea on the topic.
    Given the distance of the source, at what angle will the light hit any object, namely, the earth?
    It is still unclear what the question is.
    Sonhouse appears to have taken the question to be the angle between light rays from opposite sides of the sun. Is that the question?
    I originally thought the question was what angle the light rays make with the surface of the earth, which is obviously dependent on location and time of day.
  12. Subscriber FreakyKBH
    Acquired Taste...
    16 Jul '17 08:57
    Originally posted by twhitehead
    It is still unclear what the question is.
    Sonhouse appears to have taken the question to be the angle between light rays from opposite sides of the sun. Is that the question?
    I originally thought the question was what angle the light rays make with the surface of the earth, which is obviously dependent on location and time of day.
    I'm zeroing in on the angle the light hits the surface from the sun, as a result of their distance from each other.
    It makes sense to me that the light ought to be directly parallel.
  13. 16 Jul '17 09:10
    Originally posted by FreakyKBH
    I'm zeroing in on the angle the light hits the surface from the sun, as a result of their distance from each other.
    So you mean the angle the sun subtends on the sky?
    Or do you mean the angle between two light rays that originated from one point at the sun? If the latter, then it depends on where they are striking the earth.

    It makes sense to me that the light ought to be directly parallel.
    Obviously not. We can easily measure the arc of the sun.
  14. Subscriber FreakyKBH
    Acquired Taste...
    16 Jul '17 10:42
    Originally posted by twhitehead
    So you mean the angle the sun subtends on the sky?
    Or do you mean the angle between two light rays that originated from one point at the sun? If the latter, then it depends on where they are striking the earth.

    [b]It makes sense to me that the light ought to be directly parallel.

    Obviously not. We can easily measure the arc of the sun.[/b]
    What do you mean by measuring the arc of the sun?
  15. 16 Jul '17 11:34 / 1 edit
    Originally posted by FreakyKBH
    What do you mean by measuring the arc of the sun?
    https://en.wikipedia.org/wiki/Sun_path

    you must be pretty ignorant.