ast 103 the solar system - unlv physics & …kn/ast103-s12/01_intro.pdf• bennett et al, cosmic...
TRANSCRIPT
![Page 1: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/1.jpg)
AST 103The Solar System
Pick up two items from the front table (one each):1. Syllabus
2. ABCD card
Prof. Ken NagamineDept. of Physics & Astronomy
UNLV
1
![Page 2: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/2.jpg)
Instructor Contact Info
• Prof. Ken Nagamine
• Dept. of Physics & Astronomy
• Office: BPB 242
• Tel: 895-3485
• Email: [email protected] (best way)
TA: Mr. He Gao (email: [email protected] ) office: BPB 247
2
![Page 3: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/3.jpg)
AST 103
• Class time: Mon/Wed 10:00a-11:15am (Section 1), 11:30am-12:45pm (Section 2)
• Location: BPB 102
• Office Hours: Thu 3:00-4:15pm, my office (BPB-242)
• Class website: http://www.physics.unlv.edu/~kn/AST103-S12/
3
![Page 4: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/4.jpg)
Textbooks• Bennett et al, Cosmic Perspective, 6th edition
• Prather et al, Lecture-Tutorials for Introductory Astronomy, 2nd edition - BRING THIS TO CLASS EVERY DAY
4
![Page 5: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/5.jpg)
What should you do?
• Read the textbook before class (lecture notes will be uploaded to the class website)
• Attend lectures and participate
• Complete Lecture-Tutorials with a partner or your study group
• Ask questions if not clear; PARTICIPATE!
• Take tests and the final exam
5
![Page 6: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/6.jpg)
A look at the Syllabus
This is our contract with one another!
Note the Test days and the Final Exam date!
6
![Page 7: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/7.jpg)
Lecture Tutorials
What is it?
7
![Page 8: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/8.jpg)
Key results from cognitive science and education research
• Learning is constructive - learning requires mental effort
• Most people require some social interactions in order to learn effectively
8
![Page 9: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/9.jpg)
Former students speak out• “I liked the Tutorial, they were very helpful. I
am not a science person but feel that I learned a lot from them.
• “Why don’t all professors use tutorials during class?”
• “The student interaction and tutorials are a very effective approach to both teaching and learning. I guarantee most students will retain most of this course.”
9
![Page 10: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/10.jpg)
• “And then the tutorials? I don’t know who ever thought of that. But it’s really how classes should be taught… The tutorials break down the concepts. You start with something so simple…and then it slowly gets to more complicated.”
Former students speak out
10
![Page 11: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/11.jpg)
Any Questions?
11
![Page 12: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/12.jpg)
Find your partners and form study groups to do
the lecture tutorials.3 min
12
![Page 13: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/13.jpg)
OverviewChapter 1
Our Place in the Universe
13
![Page 14: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/14.jpg)
1.1 A Modern View of the Universe
• What is our place in the universe?• How did we come to be?• How can we know what the universe was
like in the past?• Can we see the entire universe?
Our goals for learning:
14
![Page 15: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/15.jpg)
15
![Page 16: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/16.jpg)
Hierarchy of Structure
~104 km
~1010 km
~1018 km
~1019 km~1021 km
-- our place in the Universe
16
![Page 17: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/17.jpg)
Planet
A moderately large object that orbits a star; it shines by reflected light. Planets may be rocky, icy, or
gaseous in composition.
Mars Neptune
17
![Page 18: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/18.jpg)
Moon (or satellite)
An object that orbits a planet.
Ganymede (orbits Jupiter)
18
![Page 19: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/19.jpg)
19
![Page 20: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/20.jpg)
A large, glowing ball of gas that generates heat and light through nuclear fusion
Star (Sun is one of them)
20
![Page 21: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/21.jpg)
The Solar system
1 AU
1 AU(astronomical unit)= 1.5x108 km
40AU0.4
0.7
1.0AU
1.5
5.2 9.5 19 30
A star and all the material that orbits it, including its planets and moons
21
![Page 22: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/22.jpg)
The ABCD card
• Fold your card so that at any time, you can display any of the four letters.
• Write your name on the back.
• BRING THIS TO CLASS EVERY DAY!!
• If you lose it, the second copy will be $1.
22
![Page 23: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/23.jpg)
The definition of one astronomical unit is
(a) any planet’s average distance from the Sun.
(b) Earth’s average distance from the Sun.
(c) any large astronomical distance.
Quiz
23
![Page 24: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/24.jpg)
Ida
Asteroid
A relatively small and rocky object that orbits a star.
253 Mathilde, an asteroid measuring about 50 kilometers (31.1 miles) across. Photograph taken in 1997 by the NEAR Shoemaker probe.
24
![Page 25: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/25.jpg)
Comet
A relatively small and icy object that orbits a star.
25
![Page 26: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/26.jpg)
Nebula
An interstellar cloud of gas and/or dust
26
![Page 27: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/27.jpg)
GalaxyA great island of stars in space, all held
together by gravity and orbiting a common center
M31, The Great Galaxy in Andromeda
27
![Page 28: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/28.jpg)
Universe
The sum total of all matter and energy; that is, everything within and between
all galaxies
28
![Page 29: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/29.jpg)
Now, some basic stuff.
29
![Page 30: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/30.jpg)
SI units (Systeme Internationale d’Unites)(International System of Units; established 1960)
• Length -- Meters (m)
• 1 mile = 1609m = 1.609 km (kilo=1000)
• Mass -- Kilograms (kg)
• 1 kg = 2.205 lb, 1 lb = 0.454 kg
• Time -- Seconds (s)
30
![Page 31: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/31.jpg)
Scientific Notation(Appendix C.2)
• Express numbers in the general form of
A x 10n
which is convenient for both large and small numbers
3,042 3.042 x 103
0.0012 1.2 x 10-3
428 ???
31
![Page 32: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/32.jpg)
Powers of Ten
5
Scientific Notation
Express numbers in a general form,
A ! 10n,
which is convenient for both large and small
numbers.
?2.3 ! 102
0.000232.3 ! 10-4
23000000000000002.3 ! 1015
23002.3 ! 103
Powers of Ten
Tteraa trillion10121,000,000,000,000
Ggigaa billion1091,000,000,000
Mmegaa million1061,000,000
Kkilo-a thousand1031,000
one1001
ccenti-a hundredth10-20.01
mmilli-a thousandth10-30.001
!micro-a millionth10-60.000001
nnano-a billionth10-90.000000001
6.4 ! 106 m 6.9 ! 108 m
5.9 ! 1012 m ~ 1021 m
32
![Page 33: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/33.jpg)
Astronomer’s Units • Astronomical Unit (AU)
• Light year (lyr)
• Parsec (pc)
1 AU ≅ 1.5 x 108 km
1 lyr = 9.5 x 1012 km
1 pc = 3.26 lyr = 3.086 x 1016 meter
Nearest star (alpha centauri) is 4.4 lyrs away.
33
![Page 34: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/34.jpg)
You are deciding which computer to buy, based on how long it takes to start running your favorite computer game. Which computer starts your game program the most quickly?
a) Game starts in 1 centisecond.
b) Game starts in 1 kilosecond.
c) Game starts in 1 microsecond.
d) Game starts in 1 millisecond.
e) Game starts in 1 second. [to choose (e), show a white side]
34
![Page 35: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/35.jpg)
Which of the following correctly lists our “cosmic address” from small to large?
a) Earth, solar system, Milky Way Galaxy, Local Group, Local Supercluster, universe
b) Earth, solar system, Local Group, Local Supercluster, Milky Way Galaxy, universe
c) Earth, Milky Way Galaxy, solar system, Local Group, Local Supercluster, universe
Quiz
35
![Page 36: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/36.jpg)
How can we know what the universe was like in the past?
• Light travels at a finite speed (300,000 km/s).
• Thus, we see objects as they were in the past:The farther away we look in distance,
the further back we look in time.
Destination Light travel time
Moon 1 secondSun 8 minutesSirius 8 yearsAndromeda Galaxy 2.5 million years
36
![Page 37: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/37.jpg)
Example:
We see the Orion Nebula as it looked 1,500 years ago.
M31, The Great Galaxy in Andromeda
37
![Page 38: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/38.jpg)
Example:This photo shows the Andromeda Galaxy as it looked about
2 1/2 million years ago. Question: When will be able to see what it looks like now?
M31, The Great Galaxy in Andromeda
38
![Page 39: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/39.jpg)
Light-year• The distance light can travel in one year.• About 10 trillion km (6 trillion miles).
1 lyr = 9.5 x 1012 km
Nearest star (alpha centauri) is 4.4 lyrs away.
39
![Page 40: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/40.jpg)
• At great distances, we see objects as they were
when the universe was much younger.
40
![Page 41: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/41.jpg)
Can we see the entire universe?
41
![Page 42: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/42.jpg)
A. Because no galaxies exist at such a great distance.B. Galaxies may exist at that distance, but their light
would be too faint for our telescopes to see.C. Because looking 15 billion light-years away means
looking to a time before the universe existed.
QuizWhy can’t we see a galaxy 15 billion light-years away?
(Assume universe is 14 billion years old, and our technology is perfect.)
42
![Page 43: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/43.jpg)
What have we learned?
• What is our physical place in the universe?– Earth is part of the Solar System, which is in the
Milky Way galaxy, which is a member of the Local Group of galaxies in the Local Supercluster
• How did we come to be?– The matter in our bodies came from the Big Bang,
which produced hydrogen and helium– All other elements were constructed from H and He
in star and then recycled into new star systems, including our solar system
43
![Page 44: AST 103 The Solar System - UNLV Physics & …kn/AST103-S12/01_Intro.pdf• Bennett et al, Cosmic Perspective, 6th edition • Prather et al, Lecture-Tutorials for Introductory Astronomy](https://reader031.vdocuments.us/reader031/viewer/2022011900/5f0401627e708231d40bd91c/html5/thumbnails/44.jpg)
What have we learned?
• How can we know that the universe was like in the past?– When we look to great distances we are seeing
events that happened long ago because light travels at a finite speed
• Can we see the entire universe?– No, the observable portion of the universe is about
14 billion light-years in radius because the universe is about 14 billion years old
44