On April 5, 2015, the Curiosity rover took this beautiful picture on Mars. It is a misty and bluish sunset on the red planet. The photograph is part of a series of images captured with the camera's left lens located on a Curiosity mast, called Mastcam. The color obtained by the camera is very similar to that seen by the human eye, although it is a little less sensitive to the blue that people see.
The photograph was taken between dust storms. Martian dust is composed of fine particles that allow blue light to penetrate more easily into the atmosphere than other colors with longer wavelengths. This makes the blue tones of sunlight more intense, compared to a wider dispersion of the yellow and red tones. The Martian sky is blue in the late afternoon, but during the day it highlights the rusty red tone of the dust.
The reason that the sunsets on Mars are blue is that the planet is farther from the Sun than the Earth. Sunlight is dimmer and has less intensity. While on Earth the solar disk is 0.5 °, on Mars it is reduced to 0.35 °, varying the size of the particles in suspension with respect to those of the Earth's atmosphere.
This photograph was taken from the Gale crater, place of Mars where the Curiosity landed on August 6, 2012. The color of the photos was graduated, and the whites were compensated to remove artifacts from the camera. All this series of images will help researchers to evaluate the vertical distribution of dust in the Martian atmosphere.
|North Pole of Mars|