And the sad thing is, if it takes hundreds of millions of years to evolve an intelligent species, as far as we know there is absolutely no way we can leave a me

And the sad thing is, if it takes hundreds of millions of years to evolve an intelligent species, as far as we know there is absolutely no way we can leave a message to the ones who could presumably come after us. Even choosing a location on Earth for the message is impossible because even optimal places for life to flourish become deserts or buried under ice or rocks on those time scales. Makes you think how small we are. The best bet would probably be to draw a giant smiley face on the light side of the Moon - but that's assuming that a new species will have faces like ours. Maybe the "Moon rabbit" is a perfectly obvious drawing by some ancient species' standards.