Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Ast

rono

my

210

Sect

ion

1–M

WF

150

0-15

5013

4 A

stro

nom

y B

uild

ing

Thi

s C

lass

(L

ectu

re 1

5):

The

Sol

ar S

yste

m: O

verv

iew

Nex

t Cla

ss:

Plan

et P

rope

rtie

s

Mus

ic: A

my

Hit

the

Atm

osph

ere

–C

ount

ing

Cro

ws

HW

#4

due

on F

rida

y!

Tur

n in

the

Bet

elge

use

obse

rvat

ion!

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Out

line

•T

eles

cope

s

•In

trod

uctio

n to

the

Sola

r Sy

stem

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Que

stio

n

Why

wou

ld it

be

usef

ul to

pla

ce te

lesc

opes

in

spac

e?

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Opa

que

Atm

osph

ere

•T

he a

tmos

pher

e bl

ocks

som

e w

avel

engt

hs

•M

ust o

bser

ve s

ome

wav

elen

gths

fro

m s

pace

!

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Hub

ble

Spac

e T

eles

cope

•2.

5 m

eter

ref

lect

ing

tele

scop

e in

spa

ce•

Smal

l, bu

t abo

ve a

tmos

pher

e–

No

“tw

inkl

ing”

eff

ects

–N

o lig

ht p

ollu

tion

Gro

un

d-ba

sed

imag

eH

ubb

le T

eles

cope

imag

e

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Spitz

er S

pace

Tel

esco

pe

•0.

85 m

eter

infr

ared

tele

scop

e•

Lau

nche

d A

ugus

t 200

3•

Coo

led

to n

ear

abso

lute

ze

ro s

o th

at it

s ow

n he

at d

oesn

’t c

onfu

se

the

resu

lts

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Jam

es W

ebb

Spac

e T

eles

cope

•T

he n

ext s

pace

te

lesc

ope

–20

11

•O

bser

ve in

the

near

an

d m

id-i

nfra

red

•W

ill b

e th

e bi

gges

t te

lesc

ope

in s

pace

–6

met

ers!

(M

ust f

old

up f

or la

unch

)

•W

ill ta

ke 3

mon

ths

to r

each

pos

ition

–no

se

rvic

e m

issi

ons

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Laun

ched

199

9

Cra

b N

ebul

a in

X-r

ays

Cha

ndra

X-r

ay O

bser

vato

ry

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

The

Big

Pic

ture

•T

oday

, we

can

obse

rve

in a

lmos

t eve

ry p

art o

f th

e el

ectr

omag

netic

spe

ctru

m

•O

nly

100

year

s ag

o, w

e w

ere

blin

d to

the

big

pict

ure

of th

e U

nive

rse

•A

s w

e be

gin

to p

iece

toge

ther

the

big

pict

ure,

our

un

ders

tand

ing

of th

e co

smos

gro

ws

.

•B

ut th

ere

is m

ore

out t

here

than

pho

tons

too:

–N

eutr

inos

–C

osm

ic r

ays

–G

ravi

ty w

aves

•A

ll ar

e us

eful

in u

nder

stan

ding

the

Sola

r Sy

stem

!

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Wha

t’s

this

Pic

ture

of?

http

://w

ww

.whf

reem

an.c

om/d

isco

veri

ng/D

TU

/EX

MO

D36

/F36

09.H

TM

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

The

Sol

ar S

yste

mT

he S

olar

Sys

tem

•W

e no

w tu

rn o

ur a

ttent

ion

to

the

sola

r sy

stem

—ou

r ho

me!

•T

his

will

be

our

focu

s fo

r th

e ne

xt m

onth

•W

e w

ill s

tudy

the

plan

ets

by

com

pari

ng th

em to

Ear

th -

and

to e

ach

othe

r

•T

o be

tter

unde

rsta

nd o

ur p

lane

t an

d its

impo

rtan

ce.

•U

se th

e pr

esen

t to

lear

n ab

out

the

past

.

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

It’s

not

you

r pa

rent

’s S

olar

Sys

tem

It’s

not

you

r pa

rent

’s S

olar

Sys

tem

The

old

sty

le o

f te

achi

ng th

e So

lar

Syst

em

•Su

n &

9 p

lane

ts

•Se

para

te s

ectio

n on

eac

h

•M

entio

n as

tero

ids

and

com

ets

•L

ots

of c

ool f

acts

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Mer

cury

Ven

usE

arth M

ars

Jupi

ter

Satu

rnU

ranu

sN

eptu

nePl

uto

Mar

y Vin

cent

Eat

s Man

y Jelly Sa

ndw

iche

sU

nder

Nei

ghbo

rsPo

rche

s

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

My V

ery

Ene

rget

icM

othe

rJu

st Serv

edU

s Nin

ePi

zzas

Mer

cury

Ven

usE

arth M

ars

Jupi

ter

Satu

rnU

ranu

sN

eptu

nePl

uto

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

21st

Cen

tury

Vie

w

•Si

x fa

mili

es o

f th

e so

lar

syst

em–

Star

–R

ocky

pla

nets

–A

ster

oid

belt

–G

as g

iant

pla

nets

–K

uipe

r be

lt

–O

ort c

loud

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Pla

nets

Dan

ce

http

://ja

nus.

astr

o.um

d.ed

u/ja

vadi

r/or

bits

/ssv

.htm

l

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Pla

neta

ry O

rbits

•O

rbita

l (an

d m

ost r

otat

iona

l)

mot

ions

in s

olar

sy

stem

are

co

unte

r cl

ock-

wis

e in

a

flat

tene

d di

sk•

Orb

its a

re a

ctua

lly

clos

e to

cir

cles

, ex

cept

Mer

cury

and

Plu

to

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Pla

neta

ry O

rbits

•O

rbita

l (an

d m

ost r

otat

iona

l)

mot

ions

in s

olar

sy

stem

are

co

unte

r cl

ock-

wis

e in

a

flat

tene

d di

sk

•O

rbits

are

act

ually

clo

se to

cir

cles

, exc

ept

Mer

cury

and

Plu

to

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

A S

ense

of

Scal

e

•M

ost p

ictu

res

of th

e So

lar

Syst

em lo

ok

som

ethi

ng li

ke th

is…

http

://w

ww

.jpl.n

asa.

gov/

galil

eo/s

epo/

educ

atio

n/na

v/s

s2.g

if

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Not

to S

cale

!

•W

hile

the

plan

ets’

siz

esar

e sc

aled

cor

rect

ly, t

heir

di

stan

ces

are

not

•T

ake

a lit

tle b

lue

ball,

1cm

ac

ross

•Im

agin

e th

at th

e E

arth

is th

is

ball

•T

he M

oon

is 3

0cm

(1

foot

) aw

ay, a

nd a

bout

¼ th

e si

ze

of th

e bl

ue b

all

6400

km

ac

ross

1 cm

acr

oss

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Con

tinui

ng th

e Sc

ale

Imag

e

•O

n th

is s

cale

, the

Sun

is

abou

t the

siz

e of

a w

agon

w

heel

•It

is a

foo

tbal

l fie

ld a

way

fr

om th

e E

arth

•M

ercu

ry is

on

the

Sun’

s 40

-yar

d lin

e

•V

enus

is o

n E

arth

’s 3

0-ya

rd li

ne

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Con

tinui

ng th

e Sc

ale

Imag

e

•T

o pu

t the

oth

er p

lane

ts o

n th

is s

cale

, we

need

to a

dd m

ore

foot

ball

fiel

ds

•M

ars

wou

ld li

e on

the

50-y

ard

line

of th

e ne

xt f

ootb

all f

ield

•Ju

pite

r w

ould

be

5 fo

otba

ll fi

elds

fro

m th

e Su

n, a

nd a

bout

the

size

of

a so

ftba

ll

•T

o ge

t to

Satu

rn, w

e ne

ed to

jum

p ou

t to

10

foot

ball

fiel

ds f

rom

the

Sun

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Con

tinui

ng th

e Sc

ale

Imag

e

•U

ranu

s w

ould

be

abou

t 20

foot

ball

fiel

ds

from

the

Sun

•N

eptu

ne w

ould

be

abou

t 30

foot

ball

fiel

ds

away

–B

oth

abou

t the

siz

e of

a g

olfb

all

•Pl

uto

wou

ld li

e an

ave

rage

of

40 f

ootb

all

fiel

ds f

rom

the

Sun,

and

be

abou

t 2

mill

imet

ers

acro

ss•

Now

let’

s lo

ok a

t the

sol

ar s

yste

m in

a li

ttle

mor

e de

tail…

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

The

Sun

•D

omin

ates

the

sola

r sy

stem

–99

.85%

of

the

tota

l mas

s

•W

ithou

t the

Sun

’s

ener

gy, l

ife

on E

arth

co

uld

not e

xist

•B

ut th

e Su

n is

a

fair

ly ty

pica

l sta

r–

Und

erst

andi

ng th

e Su

n is

vita

l to

unlo

ckin

g th

e se

cret

s of

the

star

s

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

The

Ter

rest

rial

s

•M

ercu

ry, V

enus

, E

arth

, & M

ars

–Pl

us th

e M

oon,

if

you

wan

t

•T

he c

lose

st

plan

ets

to th

e Su

n

•Sm

all b

odie

s, m

ade

mos

tly o

f ro

ck a

nd ir

on

•V

ery

sim

ilar

to e

ach

othe

r in

ove

rall

com

posi

tion

and

stru

ctur

e

•V

astly

dif

feri

ng s

urfa

ce c

ondi

tions

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

The

Ast

eroi

ds

•M

ostly

bet

wee

n th

e or

bits

of

Mar

s an

d Ju

pite

r

•R

ocky

deb

ris

left

ove

r fr

om th

e fo

rmat

ion

of th

e so

lar

syst

em

•So

me

of th

e m

ost a

ncie

nt r

ocks

in

the

sola

r sy

stem

•T

hey

hold

the

key

to

unde

rsta

ndin

g its

for

mat

ion

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Hol

lyw

ood’

s V

iew

of

the

Ast

eroi

d B

elt

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Scie

ntif

ic V

iew

of

the

Ast

eroi

d B

elt

Scie

ntif

ic V

iew

of

the

Ast

eroi

d B

elt

500

mill

ion

mile

s50

0 m

illio

n m

iles

Tho

usan

ds o

f T

hous

ands

of

aste

roid

s …

aste

roid

s …

On

aver

age,

abo

ut

On

aver

age,

abo

ut

a m

illio

n m

iles

a m

illio

n m

iles

apar

t!ap

art!

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

The

Out

er P

lane

ts

•Y

ou’v

e pr

obab

ly

hear

d th

e ou

ter

plan

ets

refe

rred

to

as

a si

ngle

gr

oup

–T

he J

ovia

ns

–T

he G

as G

iant

s

•H

owev

er, J

upite

r an

d Sa

turn

are

ver

y di

ffer

ent

wor

lds

than

Ura

nus

and

Nep

tune

•W

e w

ill c

onsi

der

them

as

two

grou

ps

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

The

Jov

ians

•Ju

pite

r an

d Sa

turn

are

ver

y si

mila

r pl

anet

s

•B

oth

are

imm

ense

pla

nets

, 100

-300

tim

es th

e m

ass

of th

e E

arth

–B

ut, t

hey

are

com

pose

d m

ainl

y of

the

light

est s

tuff

in th

e U

nive

rse,

hyd

roge

n an

d he

lium

•W

e ca

n on

ly s

ee th

e up

per

clou

d la

yers

, no

“sur

face

”

•M

ostly

mad

e of

liqu

idhy

drog

en

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

The

Nep

tuni

ans

•U

ranu

s an

d N

eptu

ne a

re v

ery

sim

ilar

to e

ach

othe

r

•H

ave

extr

emel

y la

rge

quan

titie

s of

w

ater

–In

add

ition

to h

ydro

gen

and

heliu

m

–M

akes

them

a b

it m

ore

com

pact

than

Ju

pite

r an

d Sa

turn

•B

lue

tint c

omes

fro

m m

etha

ne in

th

e at

mos

pher

e

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

The

Out

er R

each

es

•B

eyon

d th

e or

bit o

f N

eptu

ne li

e co

untle

ss b

odie

s of

roc

k &

ice

•Pl

uto

is th

e la

rges

t of

thes

e bo

dies

–N

ot a

roc

ky p

lane

t–

Not

an

ice

gian

t

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Fir

st P

ictu

res

of P

luto

/Cha

ron

•19

95 –

Hub

ble

Spac

e T

eles

cope

infr

ared

•19

96 –

Hub

ble

Spac

e T

eles

cope

vis

ible

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5F

eb 2

3, 2

005

Ast

rono

my

210

Spri

ng 2

005

Do

we

know

of

all o

f th

e B

odie

s in

our

Sol

ar S

yste

m?

•N

o.E

ven

at in

the

21st

cent

ury,

we

are

still

di

scov

erin

g ne

w c

omet

s, o

r la

rge

aste

roid

s,

or e

ven

larg

e pl

anet

-lik

e ob

ject

s?

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

The

Kui

per

Bel

t

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

New

Dat

a--

Kui

per

Obj

ect

Qua

oar

: F

ound

200

2•

Mos

t re

cent

an

d B

IGG

EST

di

scov

ered

yet

•pr

onou

nced

kw

a-w

har

•di

amet

er o

f ab

out

800

mile

s (h

alf

of

Plu

to)

•42

AU

orb

it

http

://a

ntw

rp.g

sfc.

nasa

.gov

/apo

d/ap

0210

09.h

tml

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Qua

oar

Orb

it

http

://w

ww

.gps

.cal

tech

.edu

/~ch

ad/q

uaoa

r/

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

Qua

oar

Com

pari

son

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5F

eb 2

3, 2

005

Ast

rono

my

210

Spri

ng 2

005

Lar

ge K

BO

s

•Pl

uto

still

larg

er, b

ut n

ot b

y th

at m

uch

•N

ote:

plo

t bel

ow d

oesn

’t in

clud

e Q

uaoa

r

Feb

23,

200

5A

stro

nom

y 21

0 Sp

ring

200

5

•B

illio

ns o

f ic

y m

inor

pl

anet

s –

com

et n

ucle

i

•R

ough

ly s

pher

ical

out

to

50,0

00 A

U

•Pr

edic

ted

by J

an O

ort

•E

xpla

ins

long

-per

iod

com

ets

•N

o ob

serv

atio

ns to

dat

e.

Or

is th

ere?

Oor

t Clo

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