A star chart helps distinguish Neptune

Initially understood as a new planet, Ceres was later classed among asteroids and then as a dwarf planet.

Piazzi's discovery gave observers a new moving object whose orbit needed determination.

The discovery marked the first identification of an object in the asteroid belt.

Galle and d'Arrest found the predicted planet near a position calculated by Le Verrier.

Perturbations in Uranus's orbit had led Le Verrier and independently Adams toward a possible unseen planet.

The dated observation in Berlin followed calculations developed in France and Britain.

William Lassell detected Neptune's largest moon seventeen days after the planet's discovery.

The discovery showed that the newly identified planet has a moon.

Lassell's telescope revealed a faint moving companion near the planet.

Triton became the first known object orbiting Neptune.