The video explores how stars glow through nuclear fusion, a process occurring in their cores. It explains why stars have different brightness levels, focusing on true brightness (luminosity) and apparent brightness, which is influenced by distance from Earth. The video compares Betelgeuse and the Sun, highlighting that despite Betelgeuse's greater size and luminosity, the Sun appears brighter due to its proximity to Earth. The video concludes with a recap of these concepts.

What is a star primarily composed of?

• Oxygen and Nitrogen

• Hydrogen and Helium

• Nitrogen and Helium

• Carbon and Oxygen

What process powers the energy production in stars?

• Nuclear Fusion

• Chemical Reactions

• Nuclear Fission

• Combustion

What is the term used to describe a star's true brightness?

• Intensity

• Radiance

• Luminosity

• Apparent Brightness

Which factor is NOT considered when measuring a star's true brightness?

• Power

• Energy output

• Distance from Earth

• Surface light emission

What is the main factor affecting a star's apparent brightness?

• Temperature

• Color

• Distance from Earth

• Size

Why can't astronomers measure stars' brightness up close?

• Stars are too dim

• Stars are too far and hot

• Stars are too cold

• Stars are too small

Which star is more luminous, Betelgeuse or the Sun?

• The Sun

• Neither is luminous

• Both are equally luminous

• Betelgeuse

How much more luminous is Betelgeuse compared to the Sun?

• 1,000 times

• 100 times

• 10 times

• 100,000 times

What would happen if the Sun was as far away as Betelgeuse?

• It would appear brighter

• It would appear dimmer

• It would appear the same

• It would disappear

Why does the Sun appear brighter to us than Betelgeuse?

• The Sun is closer

• The Sun is hotter

• The Sun is more powerful

• The Sun is larger