Cerbereus, let's look at this from a hypothesis vs. explanation standpoint. You say your stance is merely a negative position, but given the weight of what you are suggesting, it actually comes out to be a stronger claim that needs positive justification. Here's why. In order to accept that all probe data from beyond our moon is faked, several incredible things would have to be true. Others have pointed this out. It would have to be the case that scientists across the entire world are involved in a conspiracy that goes back generations and requires the silence of millions of people.
Now, before you start about whistleblowers, think about history. There have been many known whistleblowers for conspiracies less elaborate than what you suggest. You mentioned Assange, but think about Watergate as well. That was an operation of much smaller scope, and involving far fewer people, than what you suggest is going on. Yet, Mark Felt (a.k.a. "Deepthroat") still came forward as an informant and told his story. For context, this happened around the same time as Mariner 9 arrived at Mars and took ~7000 low-resolution, black-and-white photographs.
What you're saying is, at a time when the US government couldn't keep someone from coming forward about breaking into the headquarters of a political party, they managed somehow to create thousands of fake Martian images without the aid of digital tools, all of which correspond to what had previously been seen by telescopes, and to this day (40 years hence!) nobody has analyzed the images and shown they were fraudulent. And that's just one space probe coming from one country. Do you understand how easy it is to spot fake photographs these days?
Not only that, but two years after Mariner 9 took its pictures, the Soviet probes Mars 4 and Mars 5 made it to Mars and took pictures of their own. Curiously, they matched up with what had already been returned by Mariner 9. It would be extremely easy to tell if they were faked using different methods than the Mariner 9 pictures, unless you are suggesting that
the US and the Soviet Union secretly collaborated to release fake Mars pictures in the mid-1970's. Again, long after the collapse of the Soviet Union and well into the era of digital photographic analysis, nobody with Photoshop and an internet connection has even suggested that the Soviet images of Mars were anything other than authentic. This includes amateur astronomy buffs, hardcore paranoid libertarians, and even people who say the Moon landings were a hoax. EVEN MOON LANDING DENIERS still admit we have sent probes past the moon.
If you can fit that into your narrative of massive international cooperation, you still have to explain all the other planets, moons, and asteroids that have been photographed by multiple sources that agree with each other, none of which show the
usual hallmarks of a fake image. They would have had to maintain this secret through multiple Presidential terms in the US, regime changes in Russia and political unrest in China, for longer than I have been alive. This would require a spectacular level of planning and organization, during decades when some people thought war among these powers may be on the horizon. Meanwhile, secrets of less complicated organizations run by the same powers still managed to go public. The Pentagon Papers. The existence of the NSA. Clinton's sex scandal. How did these comparatively minor secrets manage to get leaked, when in the background a much more complex conspiracy was happening that nobody has ever produced a shred of evidence for? Especially considering the same people were in charge of keeping all these secrets. Why have they slipped up time after time across the past 40 years, right up until Edward Snowden (who is alive and well and on vacation), but never let a peep about the most convoluted scheme in human history reach any news outlet, in the freaking age of the internet?
