bright, intrinsically powerful, shiny...
The suffix for the word luminous is "-ous."
The word "luminous" can be found in "The Giver" in the following sentence: "Jonas blinked at the luminous sun."
A plage is a bright or luminous region near the sun. It is usually related with sunspots. The word comes from French, in concrete, from the word "beach".
We could see the deep craters on the luminous moon.
dark
Some words with "lumin" as a root word include illuminate, luminous, and bioluminescent.
bright
Luminous worms hung in caves and spun light silk.
The cat's luminous green eyes shone in the dark night.
My father had a luminous watch, so in the middle of the night he could tell what time it was.
luminous
Solar, radiant, luminous, celestial.