Multiple choice general knowledge

A planet that was assumed to be closest to the sun but did not even exist actually was called

  1. zeus

  2. promethius

  3. vulcan

  4. apollo

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Vulcan was the hypothetical planet proposed to exist between Mercury and the Sun to explain discrepancies in Mercury's orbit. The planet was extensively searched for in the 19th century but did not actually exist; the orbital anomalies were later explained by Einstein's theory of general relativity.