Our Sun Sun Facts Our solar systems largest

Our Sun

Sun Facts Our solar system’s largest star. Appears brightest b/c it’s our closest star. 99. 8 % of our solar system’s TOTAL mass!!!! Because of having such a huge mass, it exerts a powerful gravitational force throughout our solar system Gravitational force decreases with distance, however, it’s still strong enough to hold all our planets (and other celestial objects) in orbit This Photo by Unknown Author is licensed under CC BY-SA-NC

More Sun Facts Can fit 1. 3 million Earth’s inside it 600 x bigger than all planets put together Does not burn like a bonfire…. if it did, it would have burned out years ago More like an endless hydrogen bomb Originated from a cloud of dust forming a sphere. Sphere got hotter and hotter until it set off a chain of nuclear explosions causing the sun to shine as it continues to do today.

Sun’s interior Not a solid surface-ball of glowing gas ¾ of sun’s mass is hydrogen ¼ of sun’s mass is helium Small amounts of other elements Has an interior Has an atmosphere (cloud of gases) This Photo by Unknown Author is licensed under CC BY-SA

Interior Core Radiation Zone Convection Zone This Photo by Unknown Author is licensed under CC BY-SA

Core Most of sun’s energy produced here cause by nuclear fusion Nuclear fusion-when H atoms join together to make helium Occurs under high pressure and high temps 15 million degrees Celsius (say what? !) which is high enough for nuclear fusion to take place Energy moves outward from core, escaping into space This Photo by Unknown Author is licensed under CC BY

Radiation zone Tightly packed gas transferred to electromagnetic radiation Dense, therefore, it takes 100, 000 years for energy to move through it This Photo by Unknown Author is licensed under CC BY

Convection zone Outermost layer Hot gases rise from this zone and cool as it reaches the top of the surface Cooler gases sink, forming loops of gas that move energy toward the sun’s surface This Photo by Unknown Author is licensed under CC BY

Sun’s atmosphere Photosphere Chromosphere Corona This Photo by Unknown Author is licensed under CC BY-SA-NC

Photosphere Inner layer Gives off visible light Gases are thick enough to be visible When we look at an image of the sun, this is the part we see Considered the sun’s “surface layer”

Chromosphere This causes the “color” during a solar eclipse Causes the reddish glow

Corona White halo around sun Means “crown” Extends into space for millions of kilometers Eventually thins into streams of electrically charged particles called solar wind This Photo by Unknown Author is licensed under CC BY-SA-NC

Sun’s features Sunspots Prominences Solar flares Solar wind This Photo by Unknown Author is licensed under CC BY-SA

Sunspots Dark spots on sun’s surface Look small- but actually larger than Earth Areas on the sun where sun’s surface are cooler than surrounding gases Gives off less light than hotter gases This Photo by Unknown Author is licensed under CC BY-SA

Sun rotates!!!! Has an axis Scientists know this because sunspots appear to move across the surface

Prominences Huge reddish loops of gas Link different sunspot regions Loops can be seen extending over edge of the sun This Photo by Unknown Author is licensed under CC BY

Solar Flares Loops in sunspots suddenly connect, releasing magnetic energy This magnetic energy heats the gas to millions of degrees causing gas to erupt into space The eruptions are called solar flares This Photo by Unknown Author is licensed under CC BY-NC-ND

Solar Wind Caused by solar flares Causes magnetic storms which can affect radio, telephone, TV signals, and electrical power problems Causes auroras-electrical currents causing the atmosphere to glow at the North and South poles A magnetic storm is a brief disturbance in the Earth’s magnetic field