Earth's sunset would look completely different if the sun were replaced by other

[Buster's Uncle]

Earth's sunset would look completely different if the sun were replaced by other stars
Business Insider
By Jessica Orwig  1 hour ago



(Flickr / Ron Almog)



One of the most spectacular times of day is when the sun sets on the horizon. Just minutes before it disappears from view, the sun lights the sky with deep oranges, reds, purples, and pinks.

This happens because of the way that molecules in Earth's atmosphere interacts with the sun's light through a process called scattering.

When a particle of light hits a molecule, it bounces off, or scatters off, of that molecule and goes in a random direction. Because blue light scatters more easily than any other color of light, the sky appears blue during the day.

But during sunset, and sunrise, the sunlight passes through more of Earth's atmosphere. As a result, the light has to bypass more air molecules before reaching us, and a larger fraction of the blue light scatters away from our eyes than during the daytime. We see what's left---red, orange, and yellow light---as the spectacular colors of sunset.

Since sunset happens on a daily basis we can sometimes take this colorful display for granted. And, in fact, if our sun were a different size, color, and temperature, our sunsets would look different.

How different? Martin Vargic with Halcyon Maps has created a series of sunsets where he replaced our sun with other stars.

In the images below, Vargic used what we know about stars and scattering to interpret what different types of stars would look like during a sunset including cooler, smaller stars like Barnard's Star, and larger, hotter stars like Aldebaran.

Vargic accounts for the class of each star, which is based on a letter scheme that astronomers use to represent a star's temperature. From hottest to coolest, the scheme goes like this: OBAFGKM.  How hot or cold a star is determines the color of light it gives off, and, therefore, what that light will look like after being filtered and bent by our atmosphere. The hottest stars are blue and white while the coolest are red.

In each image, Vargic notes the star's letter, and its mass compared to our sun in the lower left-hand corner of each sunset.



(Courtesy of Martin Vargic with Halcyon Maps)


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