[monkeydreams]

Wouldn't the star itself be the closed system? Any lifeforms within it are free to reduce their own entropy so long as they increase entropy within the system.

[Sharlin]

A star, of course, is itself almost as far from a closed system as it is possible to be in our universe.

A bomb calorimeter in a chemistry class might be approximated as a closed system for the purposes of thermodynamics. Very few things in nature can.

[nextaccountic]

The star is constantly sending stuff outside (solar wind and light / photons)