Why do exoplanet researchers often measure orbital distance in AU around distant stars?

Answer

Because the governing physics (Kepler's laws) are mathematically identical to our solar system's scale.

Exoplanet researchers apply Kepler's laws, which are mathematically simplest when the primary distance unit matches the scale of the local system, even if the star system is light-years away.

Why do exoplanet researchers often measure orbital distance in AU around distant stars?
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