THEletter01 t1_iu0mare wrote on October 27, 2022 at 5:51 PM

Reply to comment by Lord_Botond in The colors of a sunrise and sunset are caused by particles and debris in the air that filter the sunlight. As air pollution worsens, the last humans alive will witness the most beautiful sunset of all. by watermelonbi

Thank you. I came here just to say this.

fish-rides-bike t1_iu0uva6 wrote on October 27, 2022 at 6:46 PM

Also, desert dust. The Gobi, for example, makes Vancouver subsets red.

But also, air pollution has been lessening dramatically the last few decades.

THEletter01 t1_iu35jl3 wrote on October 28, 2022 at 5:16 AM

Didn’t know that about the Gobi! I always learnt that around the horizon, the sunlight has to travel through more atmosphere (draw a point on a circle, then a line perpendicular to the circle and one at an angle, draw another circle to represent the atmosphere, and you can really clearly see this effect). Because of this, when the sun is low at sunrise/sunset, it excites the molecules in the atmosphere to a further extent, and it also blocks off the blue wavelengths, making the sky red. This is why at sunset, there is a gradient of colour due to the changing ‘thickness’ of the atmosphere that light is penetrating.