characteristics of stars 4-2. constellations today we use constellations to find stars in the night...
TRANSCRIPT
Characteristics of Stars4-2
Constellations• Today we use constellations to find stars
in the night sky.
Classifying Stars
• Color
• Temperature
• Size
• Composition
• Brightness
Star Temperature
• Surface Temperature = Color
Blue-white White yellow orange red
Hottest *Sun coolest
Compare the sizes of Stars• Our Sun is a medium sized Star
What is a Star?
• Hot glowing masses of Gases
• Composition: Mostly Hydrogen and Helium
What makes a Star Shine?
• The fusion of Atoms
Hydrogen atoms fusing to form Helium
releasing Heat, Light and energy• Astronomers use a Spectroscope to determine
the composition of a Star
Star Brightness (magnitude)
• Absolute Magnitude: the “Real” brightness of the star. How much light it really gives off.(Need to know the distance to the Star)
• Apparent Magnitude: How bright the star appears to be.
Star Distance
• Measured in Light-Years
• Light-Year: The distance light travels in a year. (9.5 million million Kilometers)
5.87849981 × 1012 miles (6 trillion miles)
• Speed of light: 186,000 Miles/second 300,000 Kilometers/Second
Finding the Distance to Stars
• Parallax: The “apparent “ Shift that a star has over a period of Time
• The closer the object, the more it will shift position in the sky
*Background Star
H-R DiagramHertzsprung-Russell
• Compares star temperature and Brightness
Star Types