1801
Giuseppe Piazzi, director of the Palermo Observatory, in an engraving of 1808.Image: F. Bordiga · Public domainscience · Europe
Piazzi finds the first asteroid
On the first night of the nineteenth century, 1 January 1801, the astronomer Giuseppe Piazzi was mapping stars from the observatory in Palermo when he noticed a faint object that was not on any chart. Over the following nights it moved against the stars. He first thought it might be a comet. It was Ceres, the largest body in the belt of asteroids between Mars and Jupiter and the first to be found. It is now classed as a dwarf planet, and NASA’s Dawn spacecraft orbited it from 2015.
Source: NASA Science: Ceres ↗
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