By When the sun rises or sets, it is a beautiful sight. It goes from a bright yellow ball of light to a soft orange and pink orb as it sinks below the horizon. But what makes the sun sky turn these vivid colors? The answer is a scientific phenomenon called Rayleigh scattering.
When sunlight reaches Earth, it is scattered by all the gases and particles in our atmosphere. It is scattered more in the blue spectrum than it is in other colors, which is why we usually see the sky as blue. But as the sun moves up or down on the horizon, it is passing through different amounts of atmosphere, and it scatters differently. It can even cause the shafts of light that we see when sunlight pierces a misty forest or smog.
In the morning or early evening, the Sun has less atmosphere to pass through and is thus more easily visible. This period of time is called the ‘dawn’ or ‘sunset’ of the solar cycle and is when we get to see the chromosphere and corona.
The Sun’s chromosphere is a reddish-hued layer just above the photosphere, and the corona is a beautiful white crown with streamers that look like flower petals. The reason why the corona is much hotter than the layers immediately below it is one of the big mysteries in astronomy. The physics behind it is complicated and there are many theories, but no one really knows the source of this heat.
As the Sun gets closer to the horizon, more of its light passes through our atmosphere and is scattered more in the blue spectrum. But this also means that more of the red and yellow spectrum is able to reach our eyes, which gives us a beautiful sunset. It is also more common to see a red or orange Sun at sunrise or sunset when forest fires are burning nearby or when volcanic eruptions occur. This is because the dust particles ejected into the air by these events can reflect and scatter the light and create a stunning color display.
As we move into the final phase of this solar cycle, we are experiencing a period of higher activity than usual. This could mean more sun spots or coronal mass ejections which produce the aurora borealis. It is also a great time to be an astrophotographer and take some incredible photos of the Sun. So keep your camera ready and be sure to look up when the weather is nice, you never know what you will find in the sky above you.
