Properties of Stars: Mass (41)

Stars & Mass

• Mass: How much matter is in an object.• Main evidence for star mass is its gravity. • Gravitational effects can be observed on other

objects and be used to determine a star’s mass.

Matter & Gravity• All matter produces

gravity.• Gravitational force

depends on mass and how close the object is.– More mass = more

gravity.– Less distance between

objects = more gravity.

Einstein and Gravity

• Space and time are the same thing– Serves as the “fabric of the universe”.

• Gravity is the curving of space-time created by an object’s mass.

• Objects with greater curves will cause objects with less mass/curve to fall toward it.

• Quantum physics indicates a theoretical particle (graviton) that controls gravity.

Mass & Star Families

Main sequence stars: •Larger stars are hotter. •Mass-luminosity relationship – massive are more luminous.

Mass & Star Families (cont.)

Giants and supergiants:•Greatly vary in size•Have little mass for their size (.001-.00001 g/cm3).

Mass & Star Families (cont.)White dwarfs: ½ to 1 solar mass.•Very high density because they have a mass equal to the sun but are the size of the earth. •Teaspoon of white dwarf material: 15 tons on earth.

Mass & Star Families (cont.)

• Most common stars are red and white dwarfs– Dim stars because they are so small.

• Large stars are very rare, but are easier to see because they are so bright.

Mass Super Hero (40)

• Design a comic book hero or villain based on a science concept we just discussed.

• The superpower must relate to the science concept.

• Draw an illustration showing the hero/villain using their superpower.

• Write 4-6 sentences explaining how the illustration and superpower relate to the concept.