This true color image shows the eastern sky, 30 degrees above the horizon at 05:13 local solar time on Sol 39. The bright streaks are probably ice clouds which have formed during the night. In the true colour image, the clouds appear to be blue compared to the background. This is a real effect. Unlike the red dust, the clouds are almost invisible at infrared wavelengths.
The clouds are also moving. In order to create this image, the individual, single color, data frames have had to be shifted with respect to each other. The motion indicates that the clouds are moving from the north-east to the south-west.