plural of radio astronomer

A person who studies radio astronomy.

(Britain) An honorary title given to a leading astronomer; once the director of the Greenwich observatory.

A leader in various ancient religions which worshipped heavenly bodies as gods and goddesses.

plural of astronomer-priest

(astronomy) 149,597,870,700 metres, the approximate mean distance from the Earth to the Sun (the semi-major axis of Earth's orbit), (symbol AU), used to measure distances in the solar system.

The time it takes the Earth to pass once around the Sun, particularly a tropical, sidereal, or anomalistic year.

plural of astronomical unit

The time past mean noon of a particular day, reckoned on to twenty-four hours in mean time.

The period in which the sun is between 12° and 18° below the horizon in the morning and evening.