Here's why:

* Luminosity: Betelgeuse is a red supergiant, while Vega is a blue-white main sequence star. Red supergiants are much larger and hotter than main sequence stars, making them much more luminous.

* Absolute Magnitude: Betelgeuse has an absolute magnitude of about -5.8, while Vega has an absolute magnitude of about 0.58. A lower absolute magnitude indicates a brighter star.

However, there's a catch:

* Distance: Betelgeuse is much farther away from Earth than Vega. This means that even though Betelgeuse is much more luminous, it appears dimmer in our sky.

In summary: Betelgeuse produces more light than Vega, but Vega appears brighter in our sky because it's much closer.