Complex sentence: By far the largest of them is Triton, discovered by William Lassell on October 10,1846, just 17 days after the discovery of Neptune itself: over a century passed before the discovery of the second natural satellite, Nereid.
Split into simpler sentences: By far the largest of them is Triton, discovered by William Lassell on October 10,1846, just 17 days after the discovery of Neptune itself. Over a century passed before the discovery of the second natural satellite, Nereid.