* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Our Sun - LWC Earth Science
Survey
Document related concepts
Antikythera mechanism wikipedia , lookup
Geocentric model wikipedia , lookup
Aquarius (constellation) wikipedia , lookup
Advanced Composition Explorer wikipedia , lookup
Equation of time wikipedia , lookup
History of Solar System formation and evolution hypotheses wikipedia , lookup
Astronomical unit wikipedia , lookup
Solar System wikipedia , lookup
Formation and evolution of the Solar System wikipedia , lookup
Tropical year wikipedia , lookup
Transcript
Ch 24.3: The Sun Be able to describe the size and composition of the sun. Explain how the sun produces energy. Identify and define the layers of the sun. Our Sun How big is our star, the sun? The sun is a medium size star. – 1 million earths could fit inside the sun. What is the sun made out of? The sun is about: – 75% hydrogen – 25% helium Our Sun How old is the sun? – It is 4.5 billion years old (middle-aged). – Could last 10 billion years. What is the chemical composition of the sun? – The sun does not have a solid surface, made of only plasma (beyond gas - PLASMA) Our Sun How much of the solar system makes up the sun? – The sun contains 99.8% of the solar systems mass. How does it create energy? – Energy from the sun is made by nuclear fusion. Does our Sun spin like the Earth? This is because our Sun actually spins. (Just like our planet Earth, only much more slowly.) It takes about 27 days for the Sun to make one complete rotation. The Layers of the Sun: Because the sun is made of gas, no sharp boundaries exist between its various layers. Keeping this in mind, we can divide the sun into four parts: the solar interior; the visible surface, or photosphere; and two atmospheric layers, the chromosphere and corona. Solar Interior Core 15 Million °C Nuclear fusion – Hydrogen to Helium Parts of the Sun Core Solar Interior Radiation zone (14 – 1.5 Million °C) Convective zone (1.5 Million °C) Parts of the Sun Convective Zone Radiation Zone Core The Visible Surface Photosphere (5,500 °C) – Sphere of light – Surface of the Sun – What we see here on Earth. – It exhibits a grainy texture called granules, produced by convection. Parts of the Sun Convective Zone Radiation Zone Core Photosphere The Atmosphere Chromosphere (8,000 °C) – Color sphere – Red in color – It is a relatively thin, hot layer of incandescent gases a few thousand kilometers thick. The Atmosphere Corona (1 Million °C) – Outermost layer – Extends for millions of kilometers – Solar wind is a stream of protons and electrons ejected at high speed from the solar corona. Parts of the Sun Convective Zone Radiation Zone Chromosphere & Corona Core Photosphere You can see the chromosphere and the corona during a total solar eclipse Ch 24.3: The Sun Be able to describe the physical features on the surface of the sun. Sunspots Sunspots are dark spots on the photosphere They have cooler temperatures (3,000°C) than the photosphere. Sun Spots Sun Spots are cooler because of magnetic fields slow down convection, less heat is transferred from the core of the sun to the photosphere Sunspot Cycle Sunspots vary on a 11-year cycle At the peak of the cycle there may be more than 100 sunspots. Also at the peak of the cycle the Sun is at its brightest. Sun Spot Cycle Parts of the Sun Convective Zone Radiation Zone Chromosphere & Corona Core Sunspot Photosphere Solar Flares Sudden outward eruptions of electrically charged atomic particles During the peak in the sunspot cycle, 5 to 10 solar flares may be visible each day Parts of the Sun Convective Zone Radiation Zone Chromosphere & Corona Core Sunspot Photosphere Solar Flare Prominence Prominences are huge cloudlike arches that extend from one sunspot to another. Prominences are ionized gases trapped by magnetic fields. Parts of the Sun Convective Zone Radiation Zone Chromosphere & Corona Prominence Core Sunspot Photosphere Solar Flare Solar Wind Is a constant stream of protons and electrons ejected at high speed from the sun Auroras The result of solar flares & solar wind, are bright displays of ever-changing light caused by solar radiation interacting with the atmosphere in the region of the poles.