Stars

How do we classify Stars? Star Properties Color = _______________ Size = ________________ Number = _____________

Properties of Stars Astronomers classify stars by their color, size, and brightness. Other properties of stars are chemical composition and mass.

Color = Temperature – a stars color indicates the temperature of its’surface. The hottest stars appear ______. The cooler stars appear ______. The spectrum of color in a star is from blues to greens to yellows and reds.

----------------------- Size = Age Think: What do you think happens to the size of stars as they get older? -----------------------

Video: http://www. youtube. com/watch. v=PM9CQDlQI0A 1 Video: http://www.youtube.com/watch?v=PM9CQDlQI0A 1. What did you learn about star size? 2. How does this clip relate to what else we have been learning?

Number = Amount of Brightness The brightness of a star as viewed from Earth is dependent on many factors such as color intensity and distance. Apparent Magnitude/Brightness: the brightness of a star as it appears from Earth. The apparent magnitude/brightness decreases as its distance from you increases Absolute Magnitude/Brightness or Luminosity how bright a star really is. Which of these new words mean the same thing?

Hertzsprung-Russell Diagram (H-R Diagram)

Use your notes to compare/contrast these terms: 1. Magnitude: 2 Use your notes to compare/contrast these terms: 1. Magnitude: 2. Absolute Magnitude: 3. Apparent Magnitude: Size and Comparison of the Universe video: https://www.youtube.com/watch?v=4S69zZwYrx0