ASTR 115: Stars and galaxies

1
ASTR 115 Stars and galaxies
"We are explorers. Our curiosity propels us to
push the frontiers of human possibility and
imagination. This is the core of NASA's mission -
We dare to explore."      - Michael D.
Griffin        Former NASA Administrator        
April, 2008
Somewhere, something incredible is waiting to be
known. - Carl Sagan Astronomer
2
ASTR 115 Stars and galaxies

• Instructor Tracy Furutani (tfurutan_at_northseattle
  .edu)
• Textbook (required) Astrophysics is Easy! by
  Michael Inglis
• Course website http//facweb.northseattle.edu/tfu
  rutan
• then click on the Astronomy 115 link
• Note This a hard-link integrated studies course
  with Barbara Goldners MATH 098 class. The
  classes run concurrently.

3
Course Expectations

• Basic math skills (basic algebra, scientific
  notation, unit conversion)
• Basic writing (referencing, researching, word
  processing)
• Computer literacy (using Web resources)

4
Assignments

•  Labs Hands-on exercises to reinforce lecture
  topics. Also, time will be set aside to teach
  problem solving techniques and review relevant
  lecture material. May be done in groups or
  individually.
• Poster Project Visual presentation of the term
  project. Handout will follow. Includes the
  writing of an abstract (summary) prior to the
  presentation.
• Homework Roughly one assignment per week, to be
  done outside of class time, though you should ask
  questions related to the homework in class. May
  require some outside reading. Each person should
  turn in their own assignment.
•  

5
Course Objectives

• Explore the following topics inventory of space,
  astronomical distances, forces that govern
  matter, basics of light and matter
  (spectroscopy), astronomical instrumentation,
  structure and energy source of the sun and other
  stars, stellar birth, life and death, galactic
  structure and classification, large scale
  structure of the universe, fate of the universe.
• Learn basic problem solving techniques.
• Learn basic observing and experimental techniques.

6
Some things we will discuss
7
Some things we will discuss
8
Some things we will discuss
9
Some things we will discuss
10
Why do we have seasons on earth?

1. Change of earths distance from the sun
2. Tilt of earths rotation axis relative to its
   orbit
3. Greenhouse effect
4. Mysterious alien technology

11
Why do we have seasons on earth?

1. Change of earths distance from the sun
2. Tilt of earths rotation axis relative to its
   orbit
3. Greenhouse effect
4. Mysterious alien technology

12
Seasons
13
Will a human set foot on Mars in your lifetime?

1. Yes
2. No

14
Perspective
The Earth was small, light blue, and so
touchingly alone, our home that must be defended
like a holy relic. The Earth was absolutely
round. I believe I never knew what the word round
meant until I saw Earth from space.- Aleksei
Leonov, USSR
15
Perspective
It suddenly struck me that that tiny pea, pretty
and blue, was the Earth. I put up my thumb and
shut one eye, and my thumb blotted out the planet
Earth. I didn't feel like a giant. I felt very,
very small. Neil Armstrong (Apollo XI)
The view of the Earth from the Moon fascinated
mea small disk, 240,000 miles away. . . . Raging
nationalistic interests, famines, wars,
pestilence don't show from that distance. Frank
Borman (Apollo VIII)
16
Perspective and Scale in Our Solar System
17
Our Local Inventory
What makes up our star system?
1) A single central star of spectral class G2,
luminosity class V (yellow-dwarf, main
sequence).
2) Two sub-stellar giant planets (Jupiter
Saturn)
3) Two icy-gas hybrid planets (Uranus Neptune)
All of the above planets have large systems of
satellites some are planet-sized Io, Europa,
Ganymede, Callisto, Titan, and Triton)
4) Four much smaller rocky planets. (Mercury,
Venus, Earth, Mars)
5) Two areas of failed planetary debris a) one
rock-based (asteroid belt between Mars and
Jupiter) b) one ice-based (Kuiper Belt
starting at Neptunes orbit) .
6) Several dwarf planets (e.g., Pluto)
7) An extended distribution of ejected or
non-condensed debris (Oort Cloud)
18
Asteroid belt (rocks) between Mars and Jupiter
19
Icy Kuiper Belt Objects (KBOs) lie beyond
Neptunes orbit
20
Oort Cloud is well beyond Pluto, or Sedna, or
Eris, or any other KBO
21
Solar System (Is this scale right?)

1. Yes
2. No

22
Solar System (Is this scale right?)

1. Yes
2. NO

23
(No Transcript)
24
(No Transcript)
25
The Sun and the Solar System
Any study of the solar system must start with the
Sun..
1) The sun contains 99.9 of all the mass in the
solar system (Jupiter has most of the remaining
0.1)
2) The sun dominates energy (and light)
production at all frequencies (except in radio
waves where human activity is stronger!)
3) Solar energy largely determines the
temperatures of every object in the solar system.
4) Material from the solar atmosphere is the
dominant component of interplanetary space.
Compared to the Sun, the planets are nearly
inconsequential..
26
Neptune
Uranus
Saturn
The Sun dominates the solar system.
Jupiter
Earth
Sol
27
Our Local Inventory
Where to learn more?
www.nineplanets.org
www.earthsky.org