On July 4, 2023, the Perseverance Rover marked its 842nd day on Mars. As the red Martian sky grew dark, the robot on Mars turned its left navigation camera towards the hazy horizon and captured a unique sunset that differs from those seen on Earth.
In a single photograph, the robot captured an alien sunset, where the Martian sky radiated an unusual and cool blue hue around the sun.
If observed closely, this is unlike any Earthly sunset witnessed, and there’s a logical explanation for it.
According to ScienceAlert, Mars is further from the Sun than Earth, which means the sunlight is not much powerful and less than half of what Earth gets. Also, Mars only has a percent of Earth’s atmosphere which primarily composes carbon dioxide with traces of nitrogen and oxygen.
This means there’s a distinct interaction between sunlight and the atmosphere of both planets.
On Earth when sunlight enters its atmosphere, it interacts with oxygen, nitrogen, and other particles in the sky causing the scattering of blue light, which gives our planet its characteristic blue sky during the day.
However, as the Sun rises or sets, its light passes through more atmosphere and filters out the blue and violet wavelengths by the time the light reaches our eyes and leaves behind the warm oranges and reds as the sunsets.
The sunlight on Mars interacts with iron-rich dust suspended in the thin atmosphere instead of interacting with oxygen or nitrogen. This interaction scatters lower-frequency red light during the day, creating a red sky.
During twilight, the red light disperses, revealing a cool blue hue in the Martian sky due to the dusty haze.
An atmospheric scientist at Texas A&M University, Mark Lemmon, said that “The colors on Mars come from the fact that the very fine dust is the right size so that blue light penetrates the atmosphere slightly more efficiently. When the blue light scatters off the dust, it stays closer to the direction of the Sun than light of other colors does. The rest of the sky is yellow to orange, as yellow and red light scatter all over the sky instead of being absorbed or staying close to the Sun.” ScienceAlert reported.
Sunlight continues to hit dust high in the Martian atmosphere, resulting in a bluish haze that stays for several hours post-sunset or sunrise.
According to ScienceAlert, Twilight on Mars offers an ideal opportunity for capturing photos of dust and clouds against the dark backdrop, aiding researchers in studying the Red Planet’s atmosphere, allowing them to detect dust and ice clouds with ease.
The Curiosity rover this year captured a remarkable image of the Sun’s rays piercing through Martian twilight clouds, revealing insights into particle size changes within the clouds.
Atmospheric scientist Mark Lemmon from the Space Science Institute in Boulder, Colorado, said, “By looking at color transitions, we’re seeing particle size changing across the cloud. This tells us about the way the cloud is evolving and how its particles are changing size over time.”
For almost two decades, the Curiosity rover, the Perseverance rover, the Spirit rover, and the Opportunity rover have consistently captured Mars’ sunsets and the magnificence of the photos are undiminished.
In a single photograph, the robot captured an alien sunset, where the Martian sky radiated an unusual and cool blue hue around the sun.
If observed closely, this is unlike any Earthly sunset witnessed, and there’s a logical explanation for it.
According to ScienceAlert, Mars is further from the Sun than Earth, which means the sunlight is not much powerful and less than half of what Earth gets. Also, Mars only has a percent of Earth’s atmosphere which primarily composes carbon dioxide with traces of nitrogen and oxygen.
This means there’s a distinct interaction between sunlight and the atmosphere of both planets.
On Earth when sunlight enters its atmosphere, it interacts with oxygen, nitrogen, and other particles in the sky causing the scattering of blue light, which gives our planet its characteristic blue sky during the day.
However, as the Sun rises or sets, its light passes through more atmosphere and filters out the blue and violet wavelengths by the time the light reaches our eyes and leaves behind the warm oranges and reds as the sunsets.
The sunlight on Mars interacts with iron-rich dust suspended in the thin atmosphere instead of interacting with oxygen or nitrogen. This interaction scatters lower-frequency red light during the day, creating a red sky.
During twilight, the red light disperses, revealing a cool blue hue in the Martian sky due to the dusty haze.
An atmospheric scientist at Texas A&M University, Mark Lemmon, said that “The colors on Mars come from the fact that the very fine dust is the right size so that blue light penetrates the atmosphere slightly more efficiently. When the blue light scatters off the dust, it stays closer to the direction of the Sun than light of other colors does. The rest of the sky is yellow to orange, as yellow and red light scatter all over the sky instead of being absorbed or staying close to the Sun.” ScienceAlert reported.
Sunlight continues to hit dust high in the Martian atmosphere, resulting in a bluish haze that stays for several hours post-sunset or sunrise.
According to ScienceAlert, Twilight on Mars offers an ideal opportunity for capturing photos of dust and clouds against the dark backdrop, aiding researchers in studying the Red Planet’s atmosphere, allowing them to detect dust and ice clouds with ease.
The Curiosity rover this year captured a remarkable image of the Sun’s rays piercing through Martian twilight clouds, revealing insights into particle size changes within the clouds.
Atmospheric scientist Mark Lemmon from the Space Science Institute in Boulder, Colorado, said, “By looking at color transitions, we’re seeing particle size changing across the cloud. This tells us about the way the cloud is evolving and how its particles are changing size over time.”
For almost two decades, the Curiosity rover, the Perseverance rover, the Spirit rover, and the Opportunity rover have consistently captured Mars’ sunsets and the magnificence of the photos are undiminished.
