Explanation: Which moon is this? Earth's. Our Moon's unfamiliar appearance is due partly to an unfamiliar viewing angle as captured by a little-known spacecraft -- the Soviet Union's Zond 8 that circled the Moon in October of 1970. Pictured above , the dark-centered circular feature that stands out near the top of the image is Mare Orientale , a massive impact basin formed by an ancient collision with an asteroid . Mare Orientale is surrounded by light colored and highly textured highlands. Across the image bottom lies the dark and expansive Oceanus Procellarum , the largest of the dark (but dry) maria that dominate the side of the Moon that always faces toward the Earth. Originally designed to carry humans, robotic Zond 8 came within 1000 km of the lunar surface , took about 100 detailed photographs on film, and returned them safely to Earth within a week.

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