When the core of a star gets smaller?

The core becomes a White Dwarf the star eventually cools and dims. When it stops shining, the now dead star is called a Black Dwarf. Stage 1 – Massive stars evolve in a simlar way to a small stars until it reaces its main sequence stage (see small stars, stages 1-4).

Why is a star increasing in size when the core is shrinking?

The extra gravitational pull compresses both the core and the hydrogen-burning shell around it. As the hydrogen-burning shell becomes denser, it becomes hotter and burns hydrogen at a faster rate, making the star even brighter and larger. When the core runs out of helium to burn, it and the gas around it contracts.

What happens to the core of a star as it expands into a red giant?

The core of a red giant is contracting, but the outer layers are expanding as a result of hydrogen fusion in a shell outside the core. The star gets larger, redder, and more luminous as it expands and cools.

What happens if the core of the Sun expands?

When the sun does begin to expand, it will do so quickly, sweeping through the inner solar system in just 5 million years. The expanding sun will engulf the Earth just before it reaches the tip of the red giant phase, and the sun would still have another 0.25 AU and 500,000 years to grow.

What happens in the core of a star?

The core of a star is located inside the star in a region where the temperature and pressures are sufficient to ignite nuclear fusion, converting atoms of hydrogen into helium, and releasing a tremendous amount of heat. It’s within this region that temperatures reach 15,000,000 Kelvin and nuclear fusion can take place.

What happens when the core of a star runs out of hydrogen?

Eventually the core of the star runs out of hydrogen. When that happens, the star can no longer hold up against gravity. Its inner layers start to collapse, which squishes the core, increasing the pressure and temperature in the core of the star. At this point the star is called a red giant.

What happens to the Sun’s atmosphere as the core grows hotter?

The Sun’s temperature, which reaches around 15 million degrees Celsius in its core, steadily decreases with distance from the core, falling to 6000°C at its ‘surface’. Logically, it should therefore continue to decline in the atmosphere.

When a main sequence star depletes its core hydrogen supply what happens?

As a main sequence star depletes the supply of hydrogen in the core, thermal equilibrium unbalances and the pressure in the starís core lessens. Thermal equilibrium unbalances because the fusion of four hydrogen atoms into one helium atom decreases the number of particles present in the starís core.

What happens when the core of a star is destroyed?

Once the ready supply of hydrogen in the core is gone, nuclear processes occurring there cease. Without the outward pressure generated from these reactions to counteract the force of gravity, the outer layers of the star begin to collapse inward toward the core.

What happens when a star reaches the red giant phase?

Once a medium size star (such as our Sun) has reached the red giant phase, its outer layers continue to expand, the core contracts inward, and helium atoms in the core fuse together to form carbon. This fusion releases energy and the star gets a temporary reprieve.

What happens to the mass of a star when it cools?

Eventually, only about 20\% of the star�s initial mass remains and the star spends the rest of its days cooling and shrinking until it is only a few thousand miles in diameter. It has become a white dwarf. White dwarfs are stable because the inward pull of gravity is balanced by the electrons in the core of the star repulsing each other.

What happens to a star when the helium in its core expires?

Once the helium in the core is gone, the star will shed most of its mass, forming a cloud of material called a planetary nebula. The core of the star will cool and shrink, leaving behind a small, hot ball called a white dwarf. A white dwarf doesn’t collapse against gravity because of the pressure of electrons repelling each other in its core.