nuclear fusion and the suns energy

regents review

The Sun is a massive ball of hot gas, primarily hydrogen and helium.

Helped together by its gravity

nuclear Fusion occurs

in the suns core

Nuclear Fusion

converts hydrogen into helium, releasing immense energy and causes outward pressure that opposes the inward pull of gravity.

The sun maintains a balance

between gravity (pulling in) and fusion pressure (pushing out).

this balance

keeps the sun stable during the main sequence life stage

if outward pressure drops

gravity causes contraction → core heats up → fusion increases → pressure rises again.

if outward pressure increases

Sun expands and cools → fusion slows → pressure drops back down.

Eventually, the Sun will run out of hydrogen in its core and

Without fuel, fusion slows, gravity dominates, and the balance breaks.

The Sun will expand into a red giant, shed its outer layers, and end as a white dwarf.

The Sun’s core is an extremely high-pressure, high-temperature environment, making it ideal for

nuclear fusion to take place.

Observing other stars helps astronomers

understand the Sun's life span and internal processes.

Stars at different life stages

reveal how stars evolve and die.

a stars mass allows you to

determine its life stage

Changes in luminosity and surface temperature over time

reflect internal changes in stars

the Sun’s energy output is not constant .

and changes over time

These changes influence

Earth’s climate and space weather conditions.

Nucleosynthesis

the process by which new elements are created in stars.

Fusion releases energy which

Helps power the stars and make them shine

The amount and type of elements produced by a star

depend on its mass and stage of life.