星 (Kanji for star) | KANJIDAMAGE

Onyomi

SEI

They SAY life can only exist on planets where the sun is a star.

ほし	Star. . .but sometimes a planet. Oops! ★★★☆☆

惑星(わくせい)	planet. ★★☆☆☆ 惑 (be misguided or tempted) + 星 (star) = 惑星 (planet.)
衛星(えいせい)	satellite ★☆☆☆☆ 衛 (defense) + 星 (star) = 衛星 (satellite)
図星(ずぼし)	bullseye. ☆☆☆☆☆ KUN ON 図 (diagram/ map) + 星 (star) = 図星 (bullseye.)

	Meaning	Hint	Radical
星	star	LIFE	生
皇	emperor	KING	王

There is alien LIFE on that star, but the alien emperor is their KING.