The Mirror (U.K.) carries a story and photo of an anomaly photographed on the surface of Mars by NASA's Curiosity Rover. At the distance from which pictured - a hundred or more meters - it doesn't look exactly like a natural occurrence.
I imagine alien technology on a wrecked spacer that has lain there for centuries, perhaps with freeze-dried crew bodies inside. The result of too much science fiction read as a young person? Guilty as charged.
The find would be exciting; what if the bodies were essentially identical to ours? Maybe humans are the "gone native" descendants of survivors of an on-earth crash, eh? Perhaps marooned here by an interstellar war?