star study guide - mrs. smit's science...

Star Study GuideChapter 21 Test

Branches of Earth Science

Astronomy

The study of planets, stars, and other objects in space.

Branches of Earth Science

Lithosphere

The land masses of earth

Branches of Earth Science

Hydrosphere

The waters of the earth

Branches of Earth Science

Atmosphere

The envelope of gases that surround earth

Tools used to study stars:

Telescope

An instrument that makes distant objects appear closer

Tools used to study stars:

Spectroscope

helps astronomers determine the composition of stars by creating a spectrum

What is a spectrum?

What is a constellation?

Best Known

Constellation

What is part

of it

Ursa Major

(Big Bear)

Big Dipper

Ursa Minor

(Little Bear)

Little Dipper

4 Ways to Classify Stars:

A. Color & TemperatureB. SizeC. CompositionD. Brightness

Color & Temperature

Hottest Warm Cool Coolest

A. BLUE B. WHITE C.YELLOW D.RED

Size

Neutron~~12-15 km

White Dwarf~~ size of Earth

Medium~~Size of Sun (Most Stars)

Size

Giant~~10-1000 x’sthe sun

Super Giant~~over 1,000 x’s the sun

Brightness

Apparent Brightness

The brightness of a star as it appears on Earth.

Brightness

Absolute Brightness

The actual brightness of a star (How much light the star actually gives off)

Why is the Sun the Brightest

Because the sun is the closest star to Earth

Closer stars appear brighter (apparent magnitude)

3 factors that affect brightness

A. Temperature

B. Size

C. Distance

Composition

(Chemical Make Up)

Composition of

Stars

Percentage of

ElementHydrogen 73% (MOST)

Helium 25% (2nd Most)

Other Elements 2%

Measuring distances to stars

How to MeasurePARALLAX: the apparent change in the position of a star in the sky.

Measuring distances to stars

Unit usedLight-year: The distance that light travels in one year.

H-R Diagram

What is a graph that shows the relationship between absolute brightness and surface temperature of a star

main sequence

The area in the H-R diagram where the most stars are located.

Upper left to Lower right corner

Different Paths in

Life Cycle of a Star

The MASS of a star determines the life cycle

Which star lives longer?

Low mass stars live longer because they burn their fuel slower

Multi Star Systems

BINARY STARS

A star system with 2 stars

2 STARS

Multi Star Systems

Star Cluster

Large Group of stars

Hundreds, thousands or millions

Multi Star Systems

Galaxy

A huge collection of stars bound together by gravity

Billions of Stars

Our Galaxy

Name of

our

Galaxy

MILKY WAY GALAXY

Shape of

our

galaxy

SPIRAL GALAXY

Standard Notation

four hundred million years

400,000,000