Neptune completes its first orbit since discovery

The Guardian : The planet Neptune was discovered not by astronomers but by mathematicians, who theorized that the orbit of Uranus was shaped by the gravity of another planet even farther from the Sun than Uranus. The mathematicians, John Adams and Urbain Le Verrier, came to their conclusions separately in 1846. While Adams tried to get astronomer royal George Airy to look for the planet, Verrier announced his prediction publicly. Astronomers in Berlin looked where Verrier had suggested and found Neptune; 10 days later, William Lassell, a Liverpool brewing magnate, took a look and found not only Neptune, but a white “star” close by. He had discovered Triton, one of Neptune’s moons. Yesterday marked the first Neptunian anniversary of its discovery 164.79 (Earth) years ago: one full turn of the planet around the Sun.