July 4, 2023. While one of the great powers of planet Earth celebrated its Independence Day, MarsRover Perseverance He tested his artistic skills by taking a beautiful photo of a sunset. The photo was recently released and attracted worldwide attention; because, unlike what happens on our planet, here Sunset blue.
Actually colors Martian sky They are completely opposite to earthly ones. During the day, the environment is colored red, giving the planet a hellish appearance. However, when dawn or dusk comes, the sky turns blue. A blue sunset can be as beautiful as ours, we refer to the Perseverance trials. But, leaving aside the aesthetic part of it all, what are the reasons for these differences?
There are actually several of them. But, generally speaking, atmospheric composition This is a major factor why the sunset on Mars is so different from ours.
Colors of the earth’s sky
Before we talk about the Martian sunset captured by Perseverance, let’s look at what colors of the sky on Earth.
Although it appears yellow to us, the light of the Sun is white because it is made up of all the colors of the rainbow. You just need to see how it decomposes when passing through glass or, which is much more natural, water drops atmosphere. It consists of different frequencies, which are arranged so that the lowest ones correspond to blues and violets and the highest with tones reddish and orange.
When this light hits a surface, depending on its composition, some wavelengths are absorbed and others are reflected. we see different colors. For example, when we see something black, it means that most of the radiation has been absorbed. If it is white, then almost everything is reflected. And if it looks blue, it means it has reflected lower frequencies and absorbed higher ones. Same with all flowers.
In the case of the sky, this is not a surface, but in the atmosphere there is gas particles which light is also affected. And it is the composition of these particles that gives color to the sky. The Earth’s atmosphere consists mainly of oxygen and nitrogen. These elements tend to absorb blue frequencies and reflect red ones.
This is why we see blue skies during the day. The sun is high, above our heads, so to get to us, it needs to overcome a very small gap in the atmosphere. This means that light collides with very few particles and reaches our eyes almost untouched, reflecting their lower frequencies. In fact, you could say that the sky looks purple, but human eyes are much more sensitive to blue, which is why we see it as a characteristic turquoise hue.
On the other hand, during sunset and sunrise the sun is very low. Therefore, it should explore more atmosphere until it reaches our eyes, it will not fall straight down like the rest of the day. As it passes through more of the atmosphere, it encounters more particles that absorb the blue and violet frequencies, leaving most of the red and orange to be reflected.
Sunset on Mars captured by Perseverance
There are two reasons why the sunset of Mars is so different from ours. To begin with, the Red Planet is further from the Sun than Earth, so the amount of light hitting it varies.
But this is not the most important reason. The main reason for these differences is the composition of their atmosphere. In your case a lot iron rich powder, which acts completely opposite to oxygen and nitrogen. It tends to absorb red and reflect blue. Therefore, it leaves all the red color visible throughout the day. But in the afternoon, at sunset, light encounters many of these iron particles, which absorb the red light, leaving the bluest part of the spectrum to be reflected.
In short, what he captured Perseverance It was something like the negative of the earth’s sky. When we are red, Mars is blue, and vice versa. This makes the sunset even more beautiful and fuels the desire of so many people to see the day when, just as humanity walked on the Moon, they too will be able to walk on Martian territory.
Source: Hiper Textual
