Here's why:
* Luminosity: This is the total amount of light a star emits. Brighter stars naturally appear brighter in the sky.
* Distance: The further away a star is, the dimmer it appears. This is because the light from the star spreads out over a larger area as it travels towards us.
Think of it like a light bulb: a powerful light bulb will be brighter than a weak one, but even a powerful bulb will appear dim if you're very far away from it.
