As a result of the numerous orbiters NASA has sent to Mars we now have a detailed topographical picture of what the surface of planet looks like. We see craters both large and small, huge valleys and volcanoes of monumental proportions.
However there is one small problem. The old telescopic maps of Mars showing many light and dark features on the surface of the planet which all amateur and professional astronomers alike should be familiar with, does not in any way correlate with the new topographical maps compiled by the orbiters.
Indeed there does not appear to be even the smallest of correlations between the old telescopic and new topographical maps. But the question has to be asked, why is this the case?
With our own Moon for example the light and dark features we all can see with the naked eye correlates 100% with the features seen on the more detailed topographical maps. When a high powered telescope zooms in on the surface of the Moon the light and dark features don’t simply just disappear as if they had never existed, on the contrary they merge and fit exactly with the topographical features seen ‘close up, on zoom’. The dark features become the flat expanses of the lava plains which form the lowlands of the Moon and the brighter features are the more rugged, crater ridden highlands.
But what is worse is that some of the features seen on the old and new maps of Mars also appear to conflict with one another. For example the characteristic dark triangular feature known as Syrtis Major on the old maps now cuts the meteoritic basin Syrtis Major Planitia on the new map almost in half. This would mean that one half of the basin would be light and the other dark when the area is viewed through an Earth based telescope but through an orbiter’s camera lens there is no such distinction between the two halves of the basin.
But this doesn’t make sense! Surely any albedo effects (i.e. the effect which causes the light and dark features in the first place) present on the surface of Mars visible in the old telescopic maps should also be visible in the new orbiter based maps as well? Albedo effects simply don’t just disappear.
The next mystery regarding the Martian surface is what causes these light and dark features (albedo effects) in the first place which are visible in the old maps?
Despite numerous orbiters and landers scientists appear to be at a slight loss explaining their presence and opinion is divided as to the exact cause. The first suggestion is that perhaps light and dark shades of underlying rock is the cause. But if the light and dark features are caused by different shades of rock why do these features not disappear after the Martian dust storms which almost continually rage across the planet? Once the storm has subsided and the dust has settled the light and dark features would tend to disappear as the rock would now be covered in a layer of dust. But this never happens.
Alternatively it has been suggested that perhaps the albedo features are caused by regular sized rocks on the Martian surface, the shadows they cast causing the surrounding landscape to appear darker when viewed from a great distance. However the fault with this suggestion is that during the Martian midday these shadows, and hence the albedo features associated with them, would tend to disappear and this never happens.
But why can’t the scientists studying the surface of Mars adequately explain the cause of the albedo features present on the surface of the planet?
The next curious question concerns what the exact colour of the Martian surface and its sky should be when viewed in the photographs taken by the landers? In the Viking missions the surface is a rich iron red and the sky is pale pink:
Mars Pathfinder has the surface as a light, sandy yellow brown and the sky as a light brown:
The Mars Exploration Rovers has the surface as a medium chocolately brown and the sky as a light chocolately brown:
But why should the colour of Mars be so radically different each time? NASA has no excuse as immediately beside the remote controlled camera housed on the top of each of these landers a colour chart is always placed allowing the technicians back in ground control to properly adjust the camera with regards to colour, brightness and contrast much as you would with your own television set at home. Instead we are led to believe that the NASA technicians are completely incompetent when it comes to fine tuning their colour camera settings.
So what colour should the surface of Mars be? In truth all of these photographs are completely wrong and the surface of Mars is actually a bright orange colour. When viewed through an Earth based telescope the planet is always a bright orange and this is how it would look on its surface as well.
In my opinion the real reason why NASA got the colour of the Martian surface so wrong is because the photographs were actually shot in an Earth desert and for one reason or another the colours would not adjust properly to reveal the bright orange surface they desired.