Why Is The Sun Hot?

Question 1

Is the Sun actually a giant ball of fire burning oxygen like a massive campfire?

Accepted Answer

No, the Sun is a massive ball of plasma performing nuclear fusion, not chemical burning.

Answer

Yes, it is made of trillions of tons of wood and coal.

Answer

Yes, it is a giant ball of gasoline.

Answer

No, it is actually cold, and the heat is just an illusion.

Question 2

Roughly how hot is the absolute center (the core) of the Sun?

Accepted Answer

An absolutely terrifying 27 million degrees Fahrenheit!

Answer

About 100 degrees (like a warm summer day).

Answer

Exactly 212 degrees (boiling water).

Answer

5,000 degrees.

Question 3

What exactly happens during the process of "Nuclear Fusion"?

Accepted Answer

Two tiny Hydrogen atoms are crushed together so hard that they merge to create a new Helium atom and a massive burst of energy.

Answer

The Sun explodes and then puts itself back together.

Answer

Large rocks crash into each other to create sparks.

Answer

The Sun's gravity rubs against the planets to create friction.

Question 4

Why doesn't the Sun just fly apart and explode into space?

Accepted Answer

Its own massive, crushing gravity holds all the gas together in a perfect, glowing sphere.

Answer

It is held together by a giant invisible net.

Answer

It is frozen solid in the middle.

Answer

Space is pushing inward on it from all sides.

Question 5

What would happen if the Sun suddenly stopped performing nuclear fusion right now?

Accepted Answer

The Sun would instantly collapse under its own weight and eventually go dark and cold.

Answer

It would turn into a giant diamond.

Answer

It would turn into a massive planet like Jupiter.

Answer

It would start spinning faster and faster.

Question 6

How long does it take for the light created in the Sun's core to reach the Earth?

Accepted Answer

The light takes about 8 minutes to travel across space, but it took thousands of years to escape the Sun's core!

Answer

It reaches us instantly.

Answer

Exactly one hour.

Answer

About a year.

Question 7

Is the Sun a solid object that you could theoretically walk on?

Accepted Answer

No, it is entirely made of super-heated gas and plasma; there is no solid surface.

Answer

Yes, it is made of very hot rock.

Answer

Yes, but only at night when it cools down.

Answer

It is a hollow shell made of glass.

Question 8

What are "Solar Flares"?

Accepted Answer

Massive, violent explosions of energy and radiation that burst out of the Sun's surface and into space.

Answer

Tiny sparks caused by solar wind.

Answer

Large clouds of smoke floating near the Sun.

Answer

Bright spots where the Sun is actually cooling down.

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Why Is The Sun Hot?

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