article_snippet.sent: On Mercury - the closest planet to the sun - is a large crater 960 miles (1,550km) wide called the Caloris Basin, which Artist Frank McKeever from Florida thinks we might explore (left).
article_snippet.sent: Our planets come as close as 33.9 million miles (54.6 million km), but can be as distant as 250 million miles (400 million km).
article_snippet.sent: The icy moon of Miranda (shown), meanwhile, is the smallest and innermost of the moons of Uranus.
article_snippet.sent: The gas giant planet is seen in the distance here above the horizon of The icy moon of Miranda (shown) .