THE SUN

The Sun basics The Sun has 4 layers: Core – nuclear fusion = energy in the form of heat & light. Core is 15 million° C Photosphere – visible layer of the Sun. 5,500°C Layer we get the color of our sun from. Chromosphere – middle layer of the Sun. Has a pinkish glow – “chromo” means color hence the name chromosphere. Corona – “Crown of the Sun” particles radiate outward in various levels creating a “crown” effect. The Sun basics

The Sun has 2 zones – not considered layers The Sun has 2 zones – not considered layers. Job is to move energy “in the form of heat & light to the Photosphere. Radiative Zone – radiates energy outward Convection Zone – hot to cold – takes thousands of years for light to reach the Photosphere. The Sun basics

How does the Sun get its energy? In the core Hydrogen particles collide and form helium through fusion. This process releases energy. How does the Sun get its energy?

Core - The Sun’s core is 15 million° Celsius (28 million° Fahrenheit) Core - The Sun’s core is 15 million° Celsius (28 million° Fahrenheit). A handful of the hydrogen and helium gas in the core would weigh more than 5 pounds! 100 times denser than water. In the core the sun smashes hydrogen, which becomes helium in a process called nuclear fusion which releases energy which in turn powers the sun. Layers of the Sun

Radiative Zone – In the radiative zone, energy from the core shines outward as light. Even though this energy is moving at the speed of light (186,000 mps), it bounces back and forth in every direction because this area is so dense! It may take hundreds of thousands of years for a photon of light to travel through the radiative zone. 4.5 million degrees Fahrenheit or 9 million degrees Celsius. (Not a layer of the Sun) Zones of the Sun

Convection Zone – In the convection zone, energy has a difficult time moving outward around as light. Instead, the energy is carried outward by gas. Like warm and cool air on Earth, the convection zone’s hotter gases rise upward (like a hot air balloon) cool by releasing their heat, and then sink again. The released energy shines into space from the Photosphere as visible light. 2 million degrees Fahrenheit or 4 million degrees Celsius. (Not a layer of the Sun!) Zones of the Sun

Photosphere – “Sphere of Light” It’s 6,000 degrees Celsius here or 10,000 degrees Fahrenheit. It has “cooler” spots we call sunspots (4,000 degrees) which we can think of as magnetic “storms” on the Sun’s surface. It is also speckled all over by “convection cells” which are where hot gases rising from inside the sun dump their heat into space. The photosphere shines in mostly visible light. This is the 1st layer in the Suns atmosphere and it is the “visible” layer that we see. Photons of light released from nuclear fusion make this layer shine! Layers of the Sun

Chromosphere – “Sphere of Color” Chromosphere – “Sphere of Color”. It’s above the photosphere and it’s 50,000 degrees Fahrenheit here or 20,000 degrees Celsius. This is the 2nd layer of the Sun’s atmosphere. This layer has arcs and plumes of gases called prominences. Because it’s hotter, it shines with a lot of energetic ultraviolet light – though there is a lot of red light from hydrogen as well and gives off a pinkish glow. Can be seen during a solar eclipse along with the corona. Layers of the Sun

1) Corona – The “Crown” It’s the hottest of all the Sun’s atmosphere – 1,000,000 degrees Celsius. It’s the Sun’s crown of very hot, thin gas – gas that forms looping and arcing shapes because of the Sun’s powerful magnetic fields. Powerful explosions happen here. The corona is so hot that it shines a lot of very energetic x-rays, the kind that doctors and dentists use to see inside you. Not dense – 1 Billion times less dense than water!) The 3rd and hottest layer of the Sun’s atmosphere. Can be seen along with the chromosphere during a solar eclipse. Layers of the Sun

Sunspots: spots on the photosphere that are cooler and appear darker than surrounding areas 11 year cycle Evidence that Sun rotates – 27 days Occur with solar storms The Sun

Flares: Explosive eruptions of hot gas from Sun’s surface near sunspots which release energy – seen as jets of gas which go straight out. Creates solar wind Prominences: Explosive release of energy which creates loops of glowing gas that extend into corona, magnetic fields connecting sun spots. Even Earth could fit through the loops

Solar Wind: electrically charged particles that flow out in all directions from the corona Can form auroras on earth due to Earth’s magnetic fields at the poles Solar Wind extends to the end of the Heliosphere (this is the end of the Sun’s gravitational pull in the solar system)

Diagram of the Sun