My body in a lawn chair, with my right thumb extended out for hitchhiking, my left hand holding an American flag, and a sign in my lap saying "California or bust!"
Not a single act, but a series of actions. The rovers power down during Martian nights, right? So, during these periods, you could rearrange the rocks nearby. At first, NASA might not even pick up on the changes, but eventually, someone's bound to notice.
Imagine the buzz it would create! The scientists studying the photographs sent back by the rovers would be left scratching their heads. They'd probably first suspect some unknown natural phenomena, or even the rovers themselves, until the changes became too orchestrated to explain away. It would be a cosmic puzzle, a Martian mystery that would have them combing through data for answers.
No extraordinary or unnatural objects, just ordinary Martian rocks moved around. Instead of presenting them with an object that screams 'alien intervention,' you'd be nudging them into a mystery, all with the Martian surface's naturally occurring elements.
That would definitely fuck with NASA, i can already see Youtube Videos being made about this and their being theories and stuff. This would also be very interesting, how would the Governments react to this? How will UFO Conspiracy Theorists respond to this?
Assuming size is not an object, a pyramid; doesn't matter if it's Myan, Aztec, or Egyptian, heck make it a mix, and have it buried in a mound of dirt or in a mountain with just parts of it sticking out.
Or if we aren't going supernatural teleportation of items, I'd think something like the person who said moving rocks around, maybe lay rocks out in shapes like roads or the foundations of houses.
A sealed hab dome, containing a fish breeding tank that outputs a portion every so often into another tank, and a flock of penguins. There are also penguin shaped space suits mounted next to the air locks
Ooh. A small broken octagonal habitat shape with the fossilized remains of dolphin bones and dolphin shaped mechanized suits. As well as some kind of buried damaged “launch pad” that could fit a decent sized ship.
Wait… that would be less confusing and more exciting as a earths history kind of thing.
Why stop at spacesuit? Put lunar landing module and American flag in configuration like they were on the moon. Suggesting that moon landing was indeed a fake, and they did everything on Mars.
Something that's flying around here as well, and often. Maybe they wouldn't even realize that it doesn't belong there at first. Like a condom wrapper or a dog turd.
A pen lid with the long bit broken off, a shopping trolly token, 1 threadbare sock, a novelty rubber (eraser), and one of those black twisty wires that are used to tie up new USB cables, all sealed in a sandwich bag with 'aubergine curry' written on it in janky handwriting.
Why all this random rubbish? Because it'll absolutely screw with their brains!
I met a traveller from an antique land,
Who said—“Two vast and trunkless legs of stone
Stand in the desert. . . . Near them, on the sand,
Half sunk a shattered visage lies, whose frown,
And wrinkled lip, and sneer of cold command,
Tell that its sculptor well those passions read
Which yet survive, stamped on these lifeless things,
The hand that mocked them, and the heart that fed;
And on the pedestal, these words appear:
My name is Ozymandias, King of Kings;
Look on my Works, ye Mighty, and despair!
Nothing beside remains. Round the decay
Of that colossal Wreck, boundless and bare
The lone and level sands stretch far away.”
a rocket perfectly designed for the martian environment, so that the rocket doesnt destroy itself on launch like the starship prototype for one example, and for humans to return home from mars.
Why not the Great Wall of china? Like not the exact Great Wall of China but a duplicate of it that is one to one scale. It would be clearly visible when people are looking at Mars with relatively strong telescopes so we would know it was there long before we were there
I'd get some clay, make some nonsense sculptures, then just dot them around. There'd be whole reports written on what a triangle with a dot on it could possibly mean.