Tropical, in today's Beakful, has nothing to do with pina coladas under a palm tree on a white sandy beach with comely ladies in bikinis. There is an astronomical reason for the latitudes around the equator being called "the tropics," but you will have to wait for tomorrow's Beakful to find out.
To clarify the difference, Tropical is basically solar time, while Sidereal is based on observation of the stars.
The differences add up to about 21 minutes a year, meaning that Tropical and Sidereal observations of the sky sync up on a cycle of about 26,000 years--and we're back to precession of the equinoxes.
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