Transcript Slide 1

The
Traveling Exhibit
Science Background
Part A: Intro & Family of the Sun
The Questions Behind the Exhibit
How did our Solar System form?
What are the giant planets like?
How do scientists study far away
planets?
The Big Ideas
We study the giant planets of our
Solar System because they tell us
about the formation of solar
systems, our planet, and the
conditions necessary for life.
Someday we may answer the ageold question of whether there is
life beyond Earth.
We are developing extraordinary
new tools, techniques, and insights
for exploring these extraordinary
worlds – mini solar systems that
include many moons and
spectacular rings.
Welcome to the
Exhibit
The science background is organized by EXHIBIT AREA:
Family of the Sun (Our Place in Space)
Meet the Giants
What’s Next: Missions of Tomorrow
Front
Back
A. Family of the Sun
KEY QUESTIONS:
What is gravity?
How did life on Earth depend on giant planets?
Gravity Rules
Gravity is the attractive
force between objects that
have mass. In space, this
means that a swarm of small
objects eventually collects
into a big one under the
influence of gravity. This is
how moons, rings, planets,
and stars form.
What Is Gravity?
• Isaac Newton (1643–1727) was the
first to realize that the force that
makes things fall toward Earth also
operates on the distant Moon,
keeping it in its orbit around our
planet. This force, called gravity, is
a property of all matter. Newton’s
universal law of gravitation
describes the way gravity varies
with mass (the amount of matter)
and distance.
• Albert Einstein (1879–1955) went
further to conclude that gravity is
intimately connected to space and
time. Space is curved by the
presence of matter, which is why
moons, planets, and other objects
follow curved paths.
3. Stars and star systems orbit
the centers of galaxies
1. Moons
orbit planets
4. Galaxies orbit each
other in clusters.
2. Planets orbit stars
Can You Fill in the Blanks?
Click for Answers
Exploring the Structure of the Universe
Before entering the exhibit, fill in the blanks using the following key words.
galaxy
Universe
100 billion
orbit
Earth
solar system
Jupiter
moon
planets
star
Sun
The Sun is a _________
Our
star located at the center of our __________________.
solar system
home, called __________,
Earth is one of 9 planets that orbit around the _________.
Sun
Earth has one _________
moon that orbits around it each month, showing different
phases. Some planets have many moons that ___________
orbit around them.
________________
is the largest planet in the Solar System and has 64 moons!
Jupiter
Our sun is one of about _______________
100 billion stars contained in the spiral
_____________
we call the Milky Way. Astronomers are now discovering
galaxy
Jupiter-sized ____________
planets that orbit around some of those distant stars. Outer
space is even bigger yet because the Milky Way is only one of an estimated 100
billion (100,000,000,000) galaxies in the ______________!
Universe
Copyright 2000 Cherilynn Morrow – Used with permission
Solar System Formation
1. Something (perhaps a supernova) triggers the gravitational collapse of a nearby
interstellar cloud.
2. The cloud naturally heats up and spins faster as it collapses. Collisions between
particles flatten the cloud into a disk. The Sun and planets start to form in
this spinning, flattened disk (proto-planetary disk), with the Sun at the
hottest central part.
3. In our Solar System, Earth formed in the inner region of the disk where rocky &
metallic material could condense in the greater heat. Ices & hydrocarbons
settled in the outer regions where gas giants like Jupiter form.
Crash Course
•
The largest planet, Jupiter, exerted
a powerful gravitational influence. If
Jupiter had formed closer to the
Sun, Earth and some of the other
inner planets might have been
thrown out of the Solar System!
•
Jupiter, Saturn, Uranus, and
Neptune formed amid a blizzard of
icy particles. They swept up much of
this frozen material. But much also
collected into huge “iceballs.” The
powerful gravity of the giant worlds
flung most of the iceballs into the
outskirts of the Solar System.
•
However some were diverted
toward Earth, where they crashed
and deposited vast amounts of
water—maybe enough to fill our
oceans. Since life probably started
in the oceans, we may owe our
existence to these snowballs from
afar.
Our Place in the Solar System
Earth is one of 8 PLANETS in our SOLAR SYSTEM.
The planets orbit a central STAR we call the SUN.
Jupiter
Mercury
Saturn
Mars
Venus
Earth
Neptune
Uranus
Can you name the other planets?
Hit <RETURN> for answers
Rocky terrestrial planets
of the inner Solar System.
Gas & ice giant planets
of the outer Solar System.
Influenced by the gravity of Jupiter & Neptune, icy
comets from the outer solar system likely delivered
important ingredients for life to the young Earth
environment (e.g. water and carbon compounds).
How do we explore our Solar System?
Ground-based Telescopes
The most readily available tools for exploring the
giant worlds are ground-based telescopes. These
include mammoth instruments such as the 110foot, 500-ton Goldstone Apple Valley Radio
Telescope located in California.
Space Telescopes
One advantage of launching telescopes into space
is that they have a view unobstructed by Earth’s
atmosphere. Orbiting several hundred kilometers
above Earth is the Hubble Space Telescope, which
has captured detailed views of the giant planets
and their moons.
Space Probes
The best views of the giant worlds are from up
close. Several space probes have made the
journey to the realm of giants for “quick-look” flyby
missions or for long-duration orbiting missions.
Cassini-Huygens is a spacecraft that arrived in
orbit around Saturn in 2004.
The Sun is the ONLY star in the SOLAR SYSTEM.
Earth is the ONLY
planet in our Solar
System where we
know for sure that
life has evolved.
Our Place in the Galaxy
• The Sun is the only star in the
SOLAR SYSTEM, but it is one of
over 100 billion stars in the
GALAXY we call the Milky Way.
• Our Solar System is located
about 2/3 of the way out from
the galaxy’s center.
Artist’s Concept of our Milky Way Galaxy
• Astronomers think that most of
the stars in the Milky Way galaxy
could also have planets orbiting
around them. These are called
“extra-solar planets”.
The term “Milky Way” is used in two ways.
For purposes of this presentation, we mean the whole galaxy.
1. “Milky Way” = our entire galaxy of 100
billion stars.* Our whole Solar System
orbits once around the galaxy’s center
every 225 million years or so.
* The image above is of another spiral galaxy that
may be a lot like our own Milky Way. It would not be
possible to make such an image of our own galaxy
from within it. This galaxy is called NGC 4414.
2. “Milky Way” = the band of light and
dust that stretches across a dark night
sky.* This is just a portion of one of the
spiral arms that we can see from Earth.
* The image above is a long exposure photograph,
showing much more contrast than we would see with
our naked eye. To the eye, the “Milky Way” looks
like a faint, whitish band with a few dark patches.
Assume the Sun is the size of a large grapefruit:
Q1. About how big would
planet Earth be on this scale?
[Show size with your hands or an
object. <RETURN> for answer.]
A1: About the size of a pencil tip
Q2: On this scale, how far away
would pencil-tip “Earth” be
from the grapefruit “Sun”?
A2: About 15 meters (50 ft) away.
Pluto would be about ½ mile away.
Q3: On this scale, how far
away would the nearest star
in the Milky Way galaxy be?
A3: About 5000 km (3000 miles).
The East-West distance across the US!
Of course, the Sun
is really 10 billion
times bigger than
a grapefruit with a
14 cm diameter.
So in this scale model, the space between the Sun and the
NEAREST STAR in the Milky Way galaxy is like having one
grapefruit on the Golden Gate bridge in San Francisco, and
another grapefruit on the Brooklyn Bridge in New York.
Images of spiral galaxies make it seem like stars
are crammed closely together, but in reality
there are vast distances between them.
Our galaxy is only one of more than 100 billion
galaxies in the Universe!
All but 4 specks in this “Hubble Deep Field” image are
entire galaxies, each of them with 100 billion stars.
A. Family of the Sun
SUMMARY
Gravity is the attractive force between objects that have mass.
This is how moons, rings, planets, and stars form.
Earth is one of 8 PLANETS that orbit a STAR we call the SUN [“3rd
rock from the Sun”]
The Sun is at the center of the SOLAR SYSTEM and is the ONLY star
in the Solar System.
Our SUN is one of over 100 billion STARS in the GALAXY we call the
Milky Way
Our GALAXY is one of over 100 billion galaxies in the UNIVERSE!
Test yourself on
“Earth’s Place in
Space”
by taking a few
minutes to play
TWO ASTRONOMY
GAMES
OR
Skip ahead to
PART B: Meet the
Giants
Two Astronomy Games
Two Astronomy Games
Copyright 2004 Cherilynn Morrow – Used with permission
[email protected]
On a sheet of paper, make two columns like the ones below:
Smallest
Largest
“Small and Large”
1.
2.
3.
4.
5.
6.
7.
8.
9.
Two Astronomy Games
“Near and Far”
1.
2.
3.
4.
5.
6.
7.
8.
9.
Copyright 2004 Cherilynn Morrow – Used with permission
Closest
Farthest
[email protected]
Game # 1:
 The next slide will show 9 images
 Order the objects in these images from the smallest
object (number 1) to largest object (number 9). Use the
first column in the table you created.
 Write the letter as well as the name of the object in the
column. This way, you will have a list that you can
consult later.
Are you ready?
Two Astronomy Games
Copyright 2004 Cherilynn Morrow – Used with permission
[email protected]
A. THE SUN
B. EARTH
C. SPACE SHUTTLE
D. THE MOON
E. THE SOLAR SYSTEM
G. MARS
H. A GALAXY
F. BEARS
I. JUPITER
Press ENTER for a HINT
Mars has no oceans and the same
LAND area as Earth
Two Astronomy Games
Copyright 2004 Cherilynn Morrow – Used with permission
[email protected]
The Solution
Two Astronomy Games
Copyright 2004 Cherilynn Morrow – Used with permission
[email protected]
1F. BEARS
4G. MARS
2C. SPACE SHUTTLE
3D. THE MOON
5B. EARTH
8E. THE SOLAR SYSTEM
6I. JUPITER
9H. A GALAXY
7A. THE SUN
Two Astronomy Games
Copyright 2004 Cherilynn Morrow – Used with permission
[email protected]
Game # 2:
 The next slide will show 9 images.
 Order the objects in these images from the object
that is nearest to the surface of Earth (number 1) to
the object that is farthest from the surface of Earth
(number 9). Use the second column in the table you
created.
 It would be best to write the letter as well as the
name of the object in the column. This way, you will
have a list that you can consult later.
Are you ready?
Two Astronomy Games
Copyright 2004 Cherilynn Morrow – Used with permission
[email protected]
B. A GALAXY
A. THE SUN
C. AURORAS
Press ENTER for HINTS
If we see a whole spiral,
it can’t be our own galaxy.
D. THE MOON
Auroras occur in Earth’s
uppermost atmosphere
E. JET AIRPLANE
F. HUBBLE TELESCOPE
The Space Shuttle can visit
Hubble, but not the Moon
G. AN EAGLE
H. STARS OF THE BIG DIPPER
Stars we see are within
the Milky Way galaxy
Two Astronomy Games
I. SATURN
Saturn is 10 times farther
from the Sun than Earth
Copyright 2004 Cherilynn Morrow – Used with permission
[email protected]
The Solution
Two Astronomy Games
Copyright 2004 Cherilynn Morrow – Used with permission
[email protected]
G. AN EAGLE
E. JET AIRPLANE
F. HUBBLE TELESCOPE
I. SATURN
Two Astronomy Games
D. THE MOON
H. STARS OF THE BIG DIPPER
Copyright 2004 Cherilynn Morrow – Used with permission
C. AURORAS
A. THE SUN
B. A GALAXY
[email protected]
These games are available on-line in multiple modalities:
1.
2.
3.
4.
As
As
As
As
you see it here in PowerPoint
a downloadable card game for the exhibit floor
an on-line interactive
a classroom activity
Go to www.alienearths.org.
Click on “Traveling Exhibition” then “Education Program” then
“Activities”
Two Astronomy Games
Copyright 2004 Cherilynn Morrow – Used with permission
[email protected]