How does the Sun produce energy, and why is it bright?

How does the Sun produce energy, and why is it bright?

• A. It splits heavier elements into lighter ones producing energy.
• B. It radiates energy stored from its formation without fusion.
• C. It reflects energy from other stars.
• D. It fuses hydrogen into helium in its core, releasing energy as light and heat.

Answer: (D)

Fusion in the Sun’s core powers it and makes it bright. In the Sun, hydrogen nuclei collide and fuse to form helium through proton–proton fusion under extreme temperatures and pressures. A small amount of mass is converted into energy in these reactions, and that energy travels outward as heat and light. As it makes its way from the hot core to the surface and then escapes, it appears as visible light and other radiation, which is why the Sun shines so brightly. The other ideas don’t fit: the Sun isn’t powered by splitting heavier elements, it isn’t simply radiating energy left over from its formation, and it doesn’t shine by reflecting light from other stars.

Fusion in the Sun’s core powers it and makes it bright. In the Sun, hydrogen nuclei collide and fuse to form helium through proton–proton fusion under extreme temperatures and pressures. A small amount of mass is converted into energy in these reactions, and that energy travels outward as heat and light. As it makes its way from the hot core to the surface and then escapes, it appears as visible light and other radiation, which is why the Sun shines so brightly. The other ideas don’t fit: the Sun isn’t powered by splitting heavier elements, it isn’t simply radiating energy left over from its formation, and it doesn’t shine by reflecting light from other stars.