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In this section terms that are frequently used on this site are explained. It will be expanded over time.

Terms and their Meaning
TermsExplanationFurther Information
AU (Astronomical Unit)The astronomical unit (au) is defined by the IAU as exactly 149,597,870,700 m.It is approximately the average distance between the Earth and the Sun (about 150 billion meters).
The IAU has specified that this term is lower-case “au”, so “AU” is techincally incorrect.
JPL CNEOS (English)

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