* Energy Output: Stars produce energy through nuclear fusion in their cores. The hotter the core, the faster the fusion reactions occur, leading to a higher energy output.

* Radiation: This energy is released as light and heat (radiation). More energy means more radiation, which translates to a brighter star.

* Color: Hotter stars emit more blue light, while cooler stars emit more red light. This is why the color of a star can be a good indicator of its temperature.

It's important to note:

* Evolution: Stars evolve over time, changing their temperature and brightness as they age.

* Variable Stars: Some stars naturally pulsate, causing their brightness to vary over time.

So, while a star might appear to "dim" over time due to its natural evolution, a hotter star will always be brighter than a cooler star.