# Facts About the Sun

- Type of Star: The Sun is a G-type main-sequence star (G2V), also known as a yellow dwarf.
- Composition: The Sun is primarily composed of hydrogen (about 74%) and helium (about 24%), with trace amounts of other elements.
- Temperature:
  - The Sun's core temperature reaches about 15 million°C (27 million°F).
  - The surface temperature (photosphere) is approximately 5,500°C (9,932°F).
- Size and Mass:
  - The Sun's diameter is about 1.39 million kilometers (864,000 miles).
  - It contains 99.86% of the total mass of the solar system.
- Energy Production: The Sun generates energy through nuclear fusion, converting hydrogen into helium in its core.
- Light Travel Time: Light from the Sun takes approximately 8 minutes and 20 seconds to reach Earth.
- Age: The Sun is estimated to be 4.6 billion years old and is halfway through its life cycle.
- Rotation: The Sun rotates on its axis approximately once every 25 days at the equator and once every 36 days at the poles (differential rotation).
- Solar Activity:
  - The Sun has an 11-year solar cycle, marked by varying levels of solar activity like sunspots and solar flares.
  - Solar flares and coronal mass ejections (CMEs) can affect Earth's magnetosphere, causing geomagnetic storms.
- Role in the Solar System:
  - The Sun’s gravity holds the solar system together.
  - It provides the energy necessary for life on Earth through sunlight.

## Example Questions

- What type of star is the Sun?
- How hot is the Sun’s core?
- How long does it take for light from the Sun to reach Earth?
- What elements make up the Sun?
- How old is the Sun, and how much longer will it shine?
- What is the Sun’s diameter?
- How does the Sun generate energy?