Download A spiral galaxy?

#8 Stars and
The Milky Way Galaxy
As a Review:

What is a Solar System?
- Solar means............
Sun!
So our solar system is made up of the sun,
the 8 planets, and everything else that
travels around the sun.
The sun is the only star in our SOLAR
system, but one of billions in our galaxy
Groups of Stars = A Galaxy

What is the name of our galaxy?
Milky Way Galaxy

What type of galaxy are we in?
A spiral galaxy?

What are the other two types?
Elliptical and Irregular
Spiral galaxy
Elliptical Galaxy
Irregular Galaxy
Are we at the center of the Milky Way Galaxy?
Sorry, um, NO! Let’s draw a picture
How do we measure stars?

Hotness by color
Blue → Yellow →Red (least hot)

Brightness by Magnitude
1
= brightest (1st place winner=brightest!)
 9 = less bright (9th place not as bright as 1st)
What kind of star is ours?
The sun is a main sequence star
 Average temperature (Yellow star)
 Average size (medium sized)

Neutron stars are size of a city
 Dwarf star size of Earth
 Super giant stars 100x sun

Billions of stars out there.....

The universe has billions and billions of stars
(and countless numbers of galaxies)

In between each star is gas and dust
 Gas

is mostly H (Hydrogen) and He (Helium)
Dust & gas clump together in huge
interstellar clouds called Nebula.
VERY far away picture of our Universe with
billions and billions of stars
http://micro.magnet.fsu.edu/primer/java/scienceopticsu/powersof10/
Power
of 10
Star clouds = Nebulas

HUGE (takes light 100’s of years to cross)

Gravity pulls matter in the nebula together

Pressure from collisions pushes it back apart

All balanced until........
A nearby star explosion
upsets the balance
Nebula NGC 60
- inside the
Triangulum Galaxy
-estimated distance
2.4 million lightyears away
The "Pillars of Creation"
from the Eagle Nebula
The Eagle Nebula
in its entirety.