Hitler and his cronies were obsessed with Teutonic mythology and a mélange of mystic traditions from all around the globe. While sometimes making scornful comments to others about the “impulses” of Himmler, Haushofer, Hess, and Rosenberg, he too was a member of the Thule Gesellschaft. The humble swastika may never recover from its misuse by them, for one example, even though it had been a positive symbol in Hinduism for literally thousands of years before they expropriated it.  
Rather than India, this one is from Baalbek. Those Mystery Schools got around.
 
On the left, a rendering of a design from the Bronze Age, Azerbaijan. You can see how the swastika derived from the stylization of a fractal pattern (think of a snowflake). This is why it always was seen as an embodiment and emblem of  metaphysical principles. On the right, the proto-medicine wheel type found in the Americas, drawn for the Jesuits who accompanied the Conquistadors. 16th c.
This is the emblem of the Thule Society, the gathering place for the Seekers in the Nazi hierarchy. This particular version is from a bookplate, I believe. It is easy to see how the swastika here relates to the ones above.
Many ancient traditions and Secret Societies were investigated for “evidence” of the roots of the Master Race. Anything which might have helped them (re)write history in their own image was eagerly sought out. Many of those arcane resources contained references to Mars. Now let us just suppose that an attempt was made to gain a little more information… A camera, a rocket capable of carrying that small payload out of the earth’s gravity well, and a carefully calculated trajectory could have been brought together to send an exploratory probe out to Mars. It would have taken some pictures as it passed by and then looped around and returned. The only radio needed would have been some sort of locator beacon so the probe could be recovered. Ambitious for the time, yes, but not impossible, and there was no one on Earth who would have noticed. Let’s imagine for a moment this actually occurred. Robert Heinlein (author of the book which inspired the Tom Corbett TV series) once commented, “Once you make it to Earth orbit, out of the gravity well, you are halfway to anywhere.”.  Even if  launched so late in the war that the Reich was no more by the time the probe returned,  the men responsible for the project  were still around. They had new jobs, for new masters, courtesy of Operation Paperclip and its Soviet equivalent. Perhaps there would have even been someone listening for the ping of the locator beacon, and the film subsequently recovered. The pictures would have been far better than those from the Mariner probes. Wild speculation indeed, but also a potential explanation for the nagging feeling that Someone already had an indication of what would appear on the Mariner and Viking images. This also could have a relationship to Roswell.  
The Hartz facilities were somewhere in those lovely mountains in the distance. What? Where?  I don't see anything.

Many have theorized that the Roswell crash was somehow related to the first atom bomb tests. It happened not too far from the test area, and soon after. But, if something like the above scenario did actually occur, then the equation might be a little different. Speculating again, which of these possibilities seems more logical: that a probe left who-knows-how-long ago was alerted by the flash of a nuclear explosion and signaled a far-off civilization which then sent ships to investigate, or that a still-functional sensor on Mars detected the passage of a space craft? Which one offers a greater potential threat: a low-tech planet gaining the ability to almost certainly knock itself back to the Stone Age, or evidence of space travel by an unknown civilization? OK, that’s enough speculation for now. Let’s return to the main topic. There was a reason for mentioning that scenario, however. One of the most curious aspects of the whole NASA/Cydonia story is the continuing puzzle of, as Richard C. Hoagland puts it, “What did they know and when did they know it?”  

I’ll get right to the meat of that question. They knew a lot, but not as much as they thought they knew. There was an element of denial in what they knew, too. It was not just the Nazis who wanted to reinvent History. As to when it was known, the answer is even more infuriating- it has always been known. But in the Grand Plan of Politics, it has been covered up for hundreds of years, if not thousands. That Grand Plan is distinct from the Great Work at the core of Masonic lore, where they simply forgot what was being safeguarded so only the Secret, devoid of content, remained. The Politicians knew exactly what they were hiding; their denial was the refusal to recognize why they hid it.  

There are tantalizing clues everywhere- Werner von Braun, one of the Paperclip bunch, seemed very avid about getting to Mars. Hr didn't want to wait. In an article published in Germany in 1952, reprinted in the US a year later, "Das Marsprojekt; Studie einer interplanetarischen Expedition", he outlined such a mission in great detail.. As recounted in the official NASA history of manned spaceflight, 

"Von Braun thought it was feasible to consider reaching Mars using conventional chemical propellants, nitric acid and hydrazine. One of his major fears was that spaceflight would be delayed until more advanced fuels became available, and he was reluctant to wait for cryogenic propellants or nuclear propulsion systems to be developed. He believed that existing technology was sufficient to build the launch vehicles and spacecraft needed for a voyage to Mars in his lifetime"

Gee, why the rush, Werner? Actually, he changed his public stance on going to Mars back and forth several times after that, which sounds suspiciously like Politics. What did he know, and when?

The following story is fiction, an exercise in scenery painting. This is not  what definitely happened, it is one possible way things could have happened. Rather than attempt to outline every potential aspect of a dozen different background scenarios, or presumptively declare a particular one the “truth”, I offer a peek into the thoughts of someone who found himself faced with a unique challenge in the years following World War II. This may give you some insight into how a mixture of honorable intentions and panic led to things going so horribly astray. Whatever the actual year, whatever the actual specific trigger, I believe this is pretty close to the mark. There are some pictures included, to give you a chance to participate in the situation, and ponder what you might have done in his place. One more thing- nothing else on this website is fiction .