(astronomy) planet / (archaic) a dark horse

coming-of-age ceremony; celebrated at the age of twenty.

an adult; a grown-up

Pluto (Kuiper belt object - a dwarf planet)

a satellite (a body orbiting a larger one; man-made apparatus designed to be placed in orbit around a celestial body)

(astronomy) dwarf planet

results, score, achievements, performance, record, grades

(petrology) aqueous rock

a strong request / a demand, a claim on the basis of some authority (especially for payment)

biology