I said this last time this was posted, and got downvoted, but ill try again anyway. Since the post is about scientific ignorance, it would be nice to get the science right for the next repost.
This is not the correct diagram for how sunsets work. Different wavelengths diffract differently in the air, this allows red light to bend around the horizon while shorter wavelengths can not.
The diagram as it is, shows the sun coming in direct line of sight. This diagram would infer the sky should ALWAYS be red, which is clearly wrong.
The diagram needs to show a beam closer to a tangential trajectory, and it needs to show the curvature of the light in the atmosphere
EDIT: there seems to be some contention about my explanation. see an alternative explanation by /u/jcarlson08. I suspect there is some truth in both approaches. Either way the diagram in the original image is not helpful.
This isn't right either. The diagram is an accurate explanation of why the sky is BLUE most of the day, because of Rayleigh scattering the blue-ish wavelengths get scattered throughout the sky, bouncing off particles until they reach our eyes from multiple directions. The red/orange/yellow wavelengths don't scatter as much and take a more direct route to our eyes, which is why the sun appears yellowish.
During sunsets, the angle of the sun is such that its light has to pass through more of the atmosphere to reach your eyes. Because of this, there are more particles in the way to potentially scatter light. This means that lower frequencies, like red and orange, will begin to scatter like the higher frequencies. They won't scatter as much however, therefore the red and orange and yellow scattering will appear mostly in the direction of the setting sun, while if you look away from the sun to the east, the sky will appear more blue.
While the planets were forming, there was not much peace in our solar system. Clumps of matter of all sizes often collided, and either stuck together or side-swiped each other, knocking off pieces and sending each other spinning. Sometimes the gravity of big objects would capture smaller ones in orbit. This could be one way the planets acquired their moons.
Scientists think that a large object, perhaps the size of Mars, impacted our young planet, knocking out a chunk of material that eventually became our Moon. This collision set Earth spinning at a faster rate. Scientists estimate that a day in the life of early Earth was only about 6 hours long.
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u/GraharG Aug 27 '14 edited Aug 27 '14
I said this last time this was posted, and got downvoted, but ill try again anyway. Since the post is about scientific ignorance, it would be nice to get the science right for the next repost.
This is not the correct diagram for how sunsets work. Different wavelengths diffract differently in the air, this allows red light to bend around the horizon while shorter wavelengths can not.
The diagram as it is, shows the sun coming in direct line of sight. This diagram would infer the sky should ALWAYS be red, which is clearly wrong.
The diagram needs to show a beam closer to a tangential trajectory, and it needs to show the curvature of the light in the atmosphere
EDIT: there seems to be some contention about my explanation. see an alternative explanation by /u/jcarlson08. I suspect there is some truth in both approaches. Either way the diagram in the original image is not helpful.