Big
g Bang,
g, Black
Holes, No Math
ASTR/PHYS 109
Dr. David Toback
Lectures 2 & 3
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
1
Prep For Today (is now due) – L3
• Reading:
– Required: BBBHNM: Chapter 1-4
– Recommended Reading:
• BHOT: Chap. 1-3
• SHU: Chap. 1-2
• TOE:
TOE Chap.
Ch
1
• Pre-Lecture Reading Questions (PLRQ)
– All 5 Boot Camp quizzes
– 4 written questions following the instructions. Don’t need to
turn them in yet
• Will talk about how to turn them in later
• End of Chapter Quizzes
– None (but make sure you can see EOC 2 in eCampus)
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
4
eCampus Quizzes
•
•
•
•
There are free warm-up quizzes before the End-of-Chapter quizzes
– Need a 100% on most of them (don’t worry… most are easy if you
read
d the
th FAQ)
– In the “Quizzes” folder, then go to “Required Warm-ups and PLRQ
Practice”
There will be a course pre-test
pre test called AMS (Astronomy Misconception
Survey) AFTER you finish some of the warm-ups
– Please do your best. Won’t count as part of your grade. We just
want to know what y
you know coming
g into the course
After these are done you will get a set of PLRQ Practice quizzes
– In a sub-folder called “PLRQ Boot camp”
– Also need a p
perfect
f
score
When these are done you will be able to get to the End-of-Chapter
Quizzes
p
2 (no Chapter
p
1 quiz)
q
– First one is Chapter
– EOC quizzed due AFTER we finish the chapter in lecture
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
12
Perfect Quizzes
Bad news:
• To pass the course you need to get a
perfect score on all of them
Good news:
w
• You can take as many attempts as you
want until you get a perfect score
• I will only count your best score
I REALLY want you to learn and get
good
d grades!
d !
There will be many assignments with this
rule but not all of them (e.g.
rule,
(e g AMS)
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
13
eCampus Warm-up Assignments
• You get unlimited attempts, but
if you use more then 5 you will
have to request more attempts
• To request more attempts
f ll
follow
the
h instructions at
http //people.physics.tamu.edu/
http://people.physics.tamu.edu/
toback/109/109FAQ.shtml#Wa
rmupH lp
rmupHelp
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
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Example Warmup Help Email to
109help@physics tamu edu
109help@physics.tamu.edu
Hello,
I’ve run out of attempts of Requirements Quiz 2, and would like to request more. Here is the
question I’m struggling with Question 7
"Which assignments require you to get all the parts exactly correct in order to get a passing
score? (select all that apply). Hint: Some assignments require you to get all the parts
exactly correct to get a Passing grade. Some assignments require you to get a minimum
score (<100%) in order to get a Passing grade. While it's true that when you get a Pass
for an assignment we will give 100% of the *points*, but that isn't the same as getting all
the parts of the assignment exactly correct."
– Warm-up
Warm up and requirements quizzes - Yes.
Yes All of these require getting every question
correct.
– An End Of Chapter Quiz for every chapter (except Chapter 1) - Yes. All of these
require getting every question correct.
Yes All of these require getting every question correct.
correct
– PLRQ Boot Camp quizzes - Yes.
– PLRQ Unit 1 assignment in CPR - No. While it's true we have to pass this assignment,
we don't have to get all the parts exactly correct.
– Paper 1 assignment in CPR - No. This isn't pass/fail. We don't need to get it perfect.
No This isn
isn'tt pass/fail.
pass/fail We don
don'tt need to get
– Astronomy Misconception Survey (AMS) - No.
it perfect.
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
15
Pre-Lecture Reading Questions
• It is important to learn how to ask good science
questions, and to be well prepared for Lecture
• For
F these
th
reasons we will
ill have
h
a number
b of
f PLRQ
Assignments
• Work will be done online
– Will
ll h
have an eCampus component and
d a Calibrated
lb
d
Peer Review (CPR) component
• More on CPR later
– Assignments for each Unit of the reading
• There is a set of guidelines on what we are looking
for on the websites
– You will be responsible for reading instructions
before next class
• First assignment is BootCamp quizzes in eCampus
(after Warmups)
Big
16
• Bang,
First Black
PLRQ assignmentIntroduction
in CPR is Pass/Revise
Holes, No Math
Topic 2: Going Big
Getting Help/Additional Attempts
for Boot Camp Quizzes
•
•
•
•
Send an email at 109help@physics.tamu.edu.
Include the following:
g
– The name of the quiz you are having trouble with
– The full text of the question you are struggling with
– The Yes/No answers y
you put
p for each of the 5 rubrics questions
q
(separately), and a sentence on WHY you picked each. A single line
for each rubric question is helpful.
– The feedback from eCampus itself that the quiz gives you when it
t ll you go did
tells
didn't
't gett th
the question
ti right.
i ht Y
You can find
fi d that
th t under
d
'My Grades'. Look for the quiz and click on it. Then click on the
score (number). The attempt result will open and show all the
information,
nformat on, including
nclud ng your answers and feedback.
With that information we can usually figure out what is causing you to
struggle (and will usually just give you two more attempts).
Then again,
g
maybe
y
you
y are correct and we need to fix it in eCampus!
p
If that's the case, we'll give you extra credit!
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
17
Example Request for Additional PLRQ Attempts
Email to 109help@physics.tamu.edu
•
PLRQ Quiz - Hard
"Are cosmological
g
principles
p
p
and religion
g
totally
y incompatible,
p
, or is it possible
p
to
integrate the two?"
#1
#2
#3
#4
#5
-
Yes, they have read the material
No,, it is not exactly
y relevant to the topic
p at hand
Yes, the question is clear
Yes, reflects critical thinking
Yes, it asks for info beyond the reading
Response Feedback: This question has some parts which make it hard to
assess. It clearly is about the reading (specifically the part about the
cosmology), and it's clearly stated (we can understand what it is asking). It
certainly
y is interesting
g (many
(
y people
p p buy
y lots of books about the topic),
p ), but it's
not clear it is an interesting *science* question. Even though it is borderline,
we decide to be generous and give a Yes for Rubric 4. Rubric 5, on the other
hand, concerns whether the question is asking about "science beyond what is in
g This is not asking
g about the science beyond
y
the reading.
g Rather
the reading."
it is about the compatibility between cosmology and religion. We give it a No
for Rubric 5.
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
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End-of-Chapter Quizzes in eCampus
• There are End-of-Chapter quizzes for each
chapter
– Helps ensure you have a good knowledge of
some of the important FACTS for each
chapter
Will be done
on online,
on n , us
using
ng eCampus
ampus
–W
– Are assigned AFTER we finish the chapter
in lecture,, and due before the next lecture
– If you need more attempts, follow the
instructions on the FAQ
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
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Going Big – Chapter 2
• You have to get started
somewhere
• Start by looking at the various
thi
things
in
i the
th universe
i
– Go from sizes we know to the
VERY
E
big
• After that we
we’ll
ll do the very
small
– Chapter 3
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
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More Earth
The Earth is
a sphere
h
in
i
space
108 meters!
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
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More Drawings
Orbit of the Moon
(27 3 days)
(27.3
The Earth
109 meters, a
billion meters (a
gigameter), a
million miles
m
m
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
45
The Earth orbiting the Sun
• The Earth on its
trajectory
j
y around
the sun
• The Moon going
around the Earth
1010 meters!
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
46
Earth around the Sun
• Orbit of the
Earth
– Yellow circle is
the Moon
Moon’ss
orbit
• Orbit of Venus
1011 meters!
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
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The Inner Planets
• Mars, Earth,
Venus and
M
Mercury
orbiting
b
the Sun
• All the planets
move in the same
direction
(counterclockwise
in this picture)
• A clue?
l ?
Big Bang, Black
Holes, No Math
1012 meters!
~A billion miles!
Introduction
Topic 2: Going Big
48
The Outer
Planets
• Jupiter, Saturn,
U
Uranus
and
d
Neptune
• Again
A i all
ll move
in the same
direction!
• Look from the
side: All move in
the same plane!
Another clue?
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
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1013 meters!
Aside on why Pluto isn’t a planet
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
50
The Whole Solar System
•Mostly empty space,
but some
m stuff
ff
•Typically only 1
hydrogen atom per
cubic centimeter
(size of a standard
die)
•There
Th
iis other
th stuff
t ff
we’ll talk about like
cosmic background
g
radiation and dark
matter
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
51
1014 meters!
Mostly Empty Space
• More
interstellar
space
• The small
circle
i l iis th
the
orbit of Pluto
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
1015 meters!
~trillion miles
52
More Empty Space
On this scale the
solar system is a
tiny dot
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
1016 meters!
53
The Nearest Stars
• Alpha Centauri A,
Alpha Centauri B and
Proxima Centauri
• Proxima Centauri is
the closest at 4.0x1016
meters from the sun
• Same as 4.2 lightyears away
– (it takes light 4.2
4 2
years to get there)
– 1 light-year is
about a trillion
miles
1017 m
meters!
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
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The Brightest Stars in Our Sky
• Only the
b i ht t
brightest
stars are
shown
• Almost 2000
in reality
1018 meters!
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
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Next Round…
• Again, only
the
th
brightest
g
• ~2 million
total in this
space
1019 meters!
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
56
The Milky Way
So many stars that
they
th
y appear
app ar to be
“clouds” of stars
Much of the space
between stars
b
contains “Dark
Matter” we can
Matter
can’tt see
directly
– About 5 times
more mass in Dark
Matter than the
stars
Big Bang, Black
Holes, No Math
1020 meters!57
Introduction
Topic 2: Going Big
Our Galaxy
• Central Bulge
• Spiral arms
• The sun is in
one of the
spiral arms,
~1/3 of the way
i
inward
d f
from
edge of the disk
towards the
center
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
1021 meters!
58
Two Different Views of our Galaxy
Looking down at
th center
the
t
Looking at it
f
from
th
the
side
Very flat…
V
fl
like
lik our Solar
S l system.
Outer stars rotating the same
direction… like our solar system
Big Bang, Black
Holes, No Math
Could
C
ld the
th galaxy
l
and
d the
th solar
l
system
have something in common?
Introduction
59
Created
in similar
ways?
Topic 2: Going
Big
Looking at the “Mass” in the Galaxy
• In the previous
picture we showed
picture,
the location of the
stars
• There is a LOT
more mass in the
dark matter than
in the stars
– More on dark
matter in
Chapter 6
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
60
Our Neighbor Galaxies
• There are
dwarf galaxies
just outside
our own
• Didn’t even
know there
were other
galaxies until
g
the 1920’s
1022 meters!
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
61
The Full Size Neighbors
•Many galaxies
nearby
•Galaxies are
often
ft
f
found
d iin
“clusters”
– Can be just
a few, up
p to
thousands
h
d
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
1023 meters!
t
!
62
The Local Group
• Our galaxy (the Milky
Way)
y) is part
p
of
f a
cluster of galaxies
called the “Local
Group”
• These distant
galaxies are moving
away from us VERY
quickly
– Big
g Bang
g
1024 meters!
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
63
Our “Observable” Universe
Big Bang, Black
Holes, No Math
• 1011 galaxies (about
the same number of
stars in
i our galaxy)
l
)
• We’re on the fringe
of a very large
cluster of galaxies
called the “Local
Supercluster”
• Don’t know the true
shape and size of
the universe so we
can’t g
go any
y further
25 meters or
10
Introduction
64
22
miles across
Topic 2: Going Big 10
Lecture on Chapter
p
2
now complete
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
65
Prep For Next Time – L3
• Reading: (Was due already)
– Required: BBBHNM Unit 1 (Chapter 1-4)
– Recommended Reading:
• BHOT: Chap. 1-3
• SHU: Chap. 1-2
• TOE:
TOE Chap.
Ch
1
• Pre-Lecture Reading Questions
– All 5 Boot Camp quizzes (were due already)
– 4 written questions following the instructions (were due
already). Don’t need to turn them in yet
• Will talk about how to turn them in later
– CPR Stuff: Not yet assigned. Not open for Registration
• End of Chapter Quizzes
– If we finished Chapter 2 then end-of-chapter quiz 2 (else just
above)
Introduction
Big Bang, Black
68
Topic 2: Going Big
Holes, No Math
Full Set of Readings So Far
•Required: BBBHNM: Chap 1-4
•Recommended:
R
d d
– BHOT: Chap.
p 1-3
– SHU: Chap. 1-2
– TOE: Chap
Chap. 1
Big Bang, Black
Holes, No Math
Introduction
Topic 2: Going Big
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