Our Sun is the star at the center of our Solar System. It is the engine that drives our Solar System and without which life on Earth would be impossible. For us it is everything, yet it is just one of the more than 200 billion ordinary stars in our galaxy alone!- The Sun is a Yellow Dwarf star.
- In ancient Greece the sun was called Helios.
- The Romans called the Sun Sol. This alternate name is where we get the term "Solar System", which literally means system of the Sun.
- The Sun is so large that if it were hollow more that 1 million Earths would fit inside it.
- The Sun is by far the most massive body found in our Solar System. The Sun accounts for 99.8% of the total mass of all objects in the Solar System (planets, moons, asteroids etc.).
- The Earth's gravity is measured as 1 unit of gravity. The gravity on all other planets is taken as a multiple of Earth's.
- The Sun is so massive that its gravity is 27.07 times stronger than that of Earth.
- A 100 lb person on Earth would weigh 2,707 lbs on the Sun!
- The 4 fundamental states of matter in our universe are solid, liquid, gas and plasma.
- The Sun is a Plasma; it is not a solid, nor is it a gas.
- The Sun is composed of primarily Hydrogen and Helium.
- In the core of the Sun, a process called nuclear fusion takes place.
- This process converts hydrogen into helium, giving off light and heat.
- The Sun's core is close to 15.7 million ºKelvin (K) while its surface temperature is only 5,778º K or 5,505º C.
- At 5505 degrees Celsius the surface of the Sun is actually cooler than the Earth's molten liquid core.
- The Sun is believed to be roughly 4.57 billion years old.
- Every object in our Solar System orbits around the sun in a counter-clockwise direction, as viewed from above the Sun's North Pole.
- Every object orbits the Sun in an elliptical (oval) orbit, not a perfectly round orbit.
- The average distance from the Earth to the Sun is 92, 955,807.3 miles and is called an Astronomical Unit (AU). The AU is used to measure distances throughout the Solar System.
- The distance from the Sun to the Earth is 1 AU.
- To understand the distances involved think about light. When you turn on a light in your home you see the light immediately. The light generated in the Sun must travel vast distances just to reach planet Earth.
- Travelling at the speed of light (roughly 180,000 miles per second) it still takes the light from the Sun 8 minutes to reach the Earth!
- You can imagine our Solar System as existing in a giant sort of bubble. The outer edge of this bubble is called the heliosphere.
- The edge of the heliosphere is roughly 100 astronomical units (AU) away from the Sun, or 100 times farther away than the Earth.
- Voyager 1, a spacecraft launched in 1977, is now the only manmade object to leave our Solar System! What a huge achievement for mankind!
