I stumbled upon 100 WCGU over at Julie’s Place . Here’s mine, hope you enjoy.
The rover rumbled along, vibrations working through his suit, indicating movement. The darkness was absolute, impenetrable.
“Base?” He asked, voice wavering slightly.
The com in his helmet returned only static. How much further? Dark Side Lunar One must be close. Why weren’t they responding?
He glanced at the meter on his wrist, oxygen level ticking down. “Base, tanks empty, need extract.” He knew his voice shook this time. He waited, no response.
Suddenly, the rover flipped, throwing him to bounce in a low gravity slide. He came to rest against the body of Corporal Reid.
He’d found base, too late.

I love sci-fi. There’s an interesting story in here, so much possibility.
Oh what a terrible flip that was. You write this so well, I can feel his concern turn to fear before that final flip.