A planetary prediction gets an observational test

From Palermo, Piazzi spotted an object between Mars and Jupiter that later became known as Ceres.

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.

Comparing sky positions with a chart made the new planet identifiable during the observing session.

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.