StarsStars

TemperatureTemperature Hot = blue star

(about 30,000o) Cool = red star

(about 2500o) Sun = yellow star

(about 6000o)

Hot = blue star (about 30,000o)

Cool = red star (about 2500o)

Sun = yellow star (about 6000o)

Constellation Orion Constellation Orion

BrightnessBrightness

Apparent Magnitude (m)

- The brightness of a star from a specific location

Absolute Magnitude (M)

- The brightness of a star from 10 parsecs away (32.6 light-years)

Apparent Magnitude (m)

- The brightness of a star from a specific location

Absolute Magnitude (M)

- The brightness of a star from 10 parsecs away (32.6 light-years)

BrightnessBrightness

The lower the number the brighter the star

Example: -1 is brighter than 5

The lower the number the brighter the star

Example: -1 is brighter than 5

Big DipperBig Dipper

Stellar EvolutionStellar EvolutionNebula - a

cloud of dust and gases - the birthplace of stars -”molecular cloud”

Nebula - a cloud of dust and gases - the birthplace of stars -”molecular cloud”

Eagle NebulaEagle Nebula

Stellar EvolutionStellar Evolution

Protostar - • before a real star

• temperature increasing

Protostar - • before a real star

• temperature increasing

Stellar EvolutionStellar Evolution

Main Sequence Star - fusion has begun in the core; average size & temp.; H fuses to HE

Main Sequence Star - fusion has begun in the core; average size & temp.; H fuses to HE

SunSun

Stellar EvolutionStellar EvolutionGiant or Super-giant -

all H has been fused - now fusing Helium - star begins to expand & cool

Giant or Super-giant -

all H has been fused - now fusing Helium - star begins to expand & cool

From a GiantFrom a Giant

Planetary NebulaAll Helium goneOuter gases of

star drift awayRemaining gases

collapse forming next stage

Planetary NebulaAll Helium goneOuter gases of

star drift awayRemaining gases

collapse forming next stage

…from a Planetary Nebula

…from a Planetary Nebula

White Dwarf - shrinking star

…then…*(smallest stars )

Black Dwarf - fades away

OR

*(larger small stars) Nova - explosion

White Dwarf - shrinking star

…then…*(smallest stars )

Black Dwarf - fades away

OR

*(larger small stars) Nova - explosion

…from a Supergiant…from a Supergiant

Supernova - collapse & violent explosion

Supernova - collapse & violent explosion

…from a Supernova …from a Supernova

*(smaller large stars) Neutron Star - extremely

small, dense rotating starOR

*(largest stars)Black Hole - so dense even

light can not escape

*(smaller large stars) Neutron Star - extremely

small, dense rotating starOR

*(largest stars)Black Hole - so dense even

light can not escape

All visuals are from :All visuals are from :

“Astronomy Picture of the Day” from NASA found at:

http://antwrp.gsfc.nasa.gov/apod/

“Astronomy Picture of the Day” from NASA found at:

http://antwrp.gsfc.nasa.gov/apod/