Ever since the Curiosity rover landed, NASA had been awash with new photos of the Martian landscape. Naturally, most have been black and white picks of the oxidized soil immediately around the rover’s landing area. But more have been arriving lately that show a feature unique to Mars. That feature is the Blue Sunset.
Scientists working for NASA claim that this phenomena is due to the particulate matter that is present in the Martian atmosphere. This red dust – which is composed of oxidized minerals, mainly iron – is what gives Mars its distinct color, but also provides for a fractal effect which shifts light towards the blue end of the spectrum. The same basic principle is true for sunsets seen from Earth, where our oxygen and nitrogen and ozone atmosphere causes the light to shift to the red end of the spectrum.
These patterns of Red Shift and Blue Shift are actually a very common element when it comes to astronomy. When observing galaxies in the night sky, scientists are able to tell that they are moving away because the light that they emit, and which is intercepted by our telescopes is shifted to the red end of the spectrum. Based on how much shift is occurring, scientists are bale to measure just how fast they are moving, relative to us.
When it comes time to hurl some objects into space ourselves, such as interstellar space craft, we can expect to see some of this close up. Out there, relativistic effects caused by high speeds will make the stars ahead of the ship look reddish, while stars seen to the rear will appear blue. Cool how that works huh?
To illustrate this Blue Sunset, NASA has released a compilation, time-elapse video which was taken two years ago by the Exploration Rover. It shows the sun setting in full, all the while emitting that cool, blue glow. Enjoy and stay tuned for more news on the Martian front!