Looking into the sky may not help you solve today's Tuesday Test Time challenge for today's mentalfloss.com Brain Game, but that's where you'll find the answer. Good luck!

Off the top of your head, which of
the six vowels (A, E, I, O, U, Y)
do NOT appear in the names of ANY
of the planets in our Solar System
?

Here is the ANSWER.

THE ANSWER:

O.

All other vowels appear as follows:

A (Earth, Mars, Saturn, Uranus)
E (Mercury, Venus, Earth, Jupiter, Neptune)
I (Jupiter)
U (Mercury, Venus, Jupiter, Saturn, Uranus, Neptune)
Y (Mercury)

Pluto contains the letter "O," but was reclassified as a dwarf planet in 2006.

Thanks for playing! Tomorrow, it's Wordplay Wednesday.