1. Luminosity: This is the actual amount of light a star emits. It depends on the star's size, temperature, and age. Larger, hotter, and younger stars are generally more luminous.
2. Distance: The farther a star is from Earth, the fainter it appears. This is because the light from the star spreads out over a larger area as it travels to us.
Think of it like a light bulb: a 100 watt bulb is brighter than a 25 watt bulb (luminosity). But if the 100 watt bulb is across the room, it appears dimmer than a 25 watt bulb right next to you (distance).
