A dead, or dormant, galaxy is one that no longer forms new stars.
Your prompt is DEAD GALAXY.
Elderly stars burn
A desolate galaxy
Where ancients survive
Scientist recently discovered a galaxy that stopped forming stars around thirteen billion years ago. Called JADES-GS-z7-01-QU, the galaxy is the oldest known dead galaxy to date.
Exhaustion is when
nothing new occurs to you,
nothing new occurs
Forever dimming
As the stars die one by one.
Outer dark remains.