Hectometer to Astronomical Unit Converter

A hectometer (hm) is a unit of length in the metric system equal to 100 meters. It represents an intermediate measurement between meters and kilometers.

The hectometer was established as part of the original metric system in 1795. The prefix 'hecto-' derives from the Greek word 'hekaton' meaning 'hundred'. While included in the original metric system, it has seen limited adoption compared to other metric units.

Hectometers are rarely used in everyday measurements but may appear in some agricultural contexts, land surveying, and certain engineering applications. In some countries, it's occasionally used for measuring intermediate distances in rural or agricultural settings.

An astronomical unit (AU) is a unit of length approximately equal to the average distance from Earth to the Sun, defined as exactly 149,597,870.7 kilometers or about 93 million miles.

The astronomical unit was originally defined as the semi-major axis of Earth's orbit around the Sun. It was first estimated by Giovanni Cassini in 1672 and has been refined over centuries. In 2012, the International Astronomical Union redefined it as an exact value rather than a measured quantity.

Astronomical units are primarily used for measuring distances within the solar system, including distances between planets, asteroids, and comets. They're standard in planetary science, space mission planning, and solar system astronomy.