outermost

That’s when the star goes supernova, which we can detect as soon as the bounced off material breaks through the star's outermost layer — we call this the shock breakout.

The two outermost moons, Ganymede and Callisto, are composed of about 50% water ice but likely contain rocky cores rich in elements such as carbon or silicon.

Unlike the water that falls from clouds on Earth, solar rain takes place in the Sun's corona, the outermost layer made of intensely hot plasma.

This region is essential for communication between brain networks but is also vulnerable to reduced blood flow from distal arteries, which carry blood from the heart to the outermost parts of the body.

BCC begins with abnormal growth of basal cells, which produce new skin cells when old ones die, on the outermost layer of the skin.