1. What is a star? Star- a gigantic ball of very hot gases that give off heat and light (electromagnetic radiation)  Stars are different sizes, colors, ages, and distances from Earth  Stars that are closer to Earth may appear larger, even though they are smaller than others

2. Brightness, Color, and Temperature of Stars Betelgeuse red 3,000°C Aldebaren red-orange 5,000°C Sun yellow 6,000°C Altair white 10,000°C Spica blue 35,000°C A star’s color tells you how hot it is. Red stars are the coolest. White, or blue-white stars are the hottest.

3. Let’s watch the Brain Pop Video! The Life Cycle of Stars: nebula protostar star red giant white dwarf 1 2 3 4 5 Stages of a Medium-Sized Star

4.  The Sun is actually a MEDIUM-SIZED star, but appear so large to us because it is the CLOSEST STAR to Earth.  There are Giant Stars that are 8-100 times the size of the Sun, and Supergiants that can be up to 300 times larger than the sun! How does the Sun measure up as a star?

5. Relative size of the Sun

6. The Sun’s Layers

7.  Sunspots occur in the Sun’s Photosphere. They are areas that are cooler, or not as hot, as the rest of the photosphere.  Galileo noticed these dark spots, and how they moved across the face of the sun. He realized that the sun must rotate.  Now we know that the Sun rotates at an angle, rotating more slowly at the poles than at the equator. Sunspots

8.  Loops and fountains of blazing gases may keep out of the chromosphere and reach into the corona.  These ribbons of glowing gas are called prominences.  They may last a few days or months.  Eruptions can also occur in the chromosphere, and we call these “solar flares”.  A solar flare causes a temporary bright spot in the chromosphere that can last minutes or hours.  Solar flares give off more X-rays and other electromagnetic radiation, and this can sometimes interrupt radio communication on Earth. VIDEO: http://www.space.com/27018-spectacular-august-solar-flare-wide-view-from-nasa- video.htmlhttp://www.space.com/27018-spectacular-august-solar-flare-wide-view-from-nasa- video.html Solar Eruptions

9.  A star is born in a cloud of dust and gas called a nebula.  Stars can die in different ways, depending on their mass: 1.It can use up all of its fuel (hydrogen) 2.It can become a white dwarf, explode (supernova) and leave behind a neutron star 3.It can become a black hole (the star collapses in on itself) The Life of Stars

10. The beginning of a SUPERNOVA