Transcript Notes 14-2
Notes 162 The Sun Stars an object that produces it own energy, including heat and light. The Sun is a Star • Star made of hydrogen and helium • located at the center of the solar system and is also the largest object • Has a strong gravitational pull which holds planets in orbit • 4.6 billion years old The size of the Sun • If the Sun were a hollow ball more then a million Earths could fit inside it! • The Sun is an average size star and the largest object in the solar system. • The Sun looks larger than the other stars that can be seen in the night sky because it is much closer to Earth. The sun is gas! • The Sun is a huge sphere made up of mostly of two gases. – 71% of the Sun’s mass is Hydrogen – 27% of the Sun’s mass is Helium – The remaining 2% is Oxygen and Carbon What happens inside the Sun? • Hydrogen particles smash together to make helium. • This smashing is called Nuclear Fusion. • A little bit of mass is a lost when hydrogen particles combine to make helium. • The mass in turned into energy • We see this energy as light and heat! Interior Layers: • The sun has 3 interior layers: 1) the core 2) the radiation zone 3) the convection zone The Core • Most of the energy that the Sun produces is formed in it’s core. • The Core’s temperature is 10 million to 20 million degrees Celsius. • The pressure is more than 1 billion times greater then the air pressure of Earth. Radiation Zone • Next to the core • Moves the energy produced in the core in every direction. • It can take >100,000 years for energy to move out of this layer. Convection Zone • Layer next to the radiation layer • Gasses with different energies move in circles in a way similar to air with different densities. • Energy moves out of this layer in about a week. The sun’s atmosphere: • Has 3 layers: 1) photosphere 2) chromosphere 3) corona Photosphere • Is the visible surface of the Sun. • It is not a solid surface, but rather a layer of thick gasses. • Gives off visible light Chromosphere • Is the inner layer of the Sun’s atmosphere. • When it can be seen it looks like a red circle around the Sun. The Corona • The outermost layer of the Sun’s atmosphere which creates solar winds. • The corona takes on different shapes around the Sun depending on changes in the temperature of the photosphere. Solar Flares • Are bursts (eruptions) of heat and energy that stretch out from the corona and chromospheres into space. • Sometimes the energy disrupts satellites, interfering with TV, radio, and cell phone communication systems. Aurora Borealis • Also called the Northern Lights • Energy from the solar flares increases solar winds, causing displays of differentcolored lights in the upper atmosphere. • Most often seen in Alaska, Canada, and the Northern United States Sun Spots • Solar Flares are also sometimes associated with sunspots • They are dark spots on the Sun. • They are regions of the photosphere that have a lower temperature then the surrounding regions therefore they give off less light.