Complex sentence: The Richat Structure, a prominent circular feature in the Sahara desert of Mauritania near Ouadane, has attracted attention since the earliest space missions because it forms a conspicuous bull's-eye in the otherwise rather featureless expanse of the desert.
Split into simpler sentences: The Richat Structure is a prominent circular feature in the Sahara desert of Mauritania near Ouadane. It has attracted attention since the earliest space missions because it forms a conspicuous bull's-eye in the otherwise rather featureless expanse of the desert.