This is another photo by Mark. The effect you are seeing just above the horizon is a mirage. The official name for this effect is a fata morgana. It is named after some fairy enchantress lady that was skilled in the art of changing shape, hence the name for the landscape “changing shape.” Essentially, what you are looking at is a complex mirage. I have seen several so far, all on clear days. They are evidently very rare in other parts of the world. It occurs when there are alternating warm and cold layers of air near the ground surface. Light travels through these layers and is bent towards the colder/denser air. So, when you see a fata morgana, you are actually seeing a superposition of several images of one object, in this case, part of the Transantarctic Mountains. I haven’t seen it yet, but evidently the images can change rapidly as the air layers move slightly. Every time I have seen this, the illusion has been reflected along the entire expanse of the horizon in front of the Transantarctic Mountains. This picture shows one snapshot. To capture the entire horizon at this scale would require some 20 photographs. Quite astonishing. I love this picture because it looks like an army of penguins coming to storm McMurdo.