the traveling exhibit science background part a: intro & family of the sun
TRANSCRIPT
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 IdeasWe 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 age-old 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
Family of the Sun (Our Place in Space) Meet the Giants FrontWhat’s Next: Missions of Tomorrow Back
The science background is organized by EXHIBIT AREA:
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.
• 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.
What Is Gravity?
2. Planets orbit stars
3. Stars and star systems orbit the centers of galaxies
4. Galaxies orbit each other in clusters.
1. Moonsorbit planets
Before entering the exhibit, fill in the blanks using the following key words.
galaxy orbit solar system moon star Universe Earth Jupiter planets Sun 100 billion
The Sun is a _________ located at the center of our __________________. Our
home, called __________, is one of 9 planets that orbit around the _________.
Earth has one _________ that orbits around it each month, showing different
phases. Some planets have many moons that ___________ around them.
________________ is the largest planet in the Solar System and has 64 moons!
Our sun is one of about _______________ stars contained in the spiral
_____________ we call the Milky Way. Astronomers are now discovering
Jupiter-sized ____________ 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 ______________!
Exploring the Structure of the Universe
Can You Fill in the Blanks?Click for Answers
star solar systemEarth Sunmoon
orbitJupiter
100 billiongalaxy
planets
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.
Earth is one of 8 PLANETS in our SOLAR SYSTEM. The planets orbit a central STAR we call the SUN.
Can you name the other planets?
Hit <RETURN> for answers
Mercury
Venus
Earth
Mars
Jupiter Saturn
Uranus
Neptune
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).
Our Place in the Solar System
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 110-foot, 500-ton Goldstone Apple Valley Radio
Telescope located in California.
Space TelescopesOne 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 ProbesThe 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.
• 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.
• 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”.
Artist’s Concept of our Milky Way Galaxy
Our Place in the Galaxy
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 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.
* 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.
Of course, the Sun is really 10 billion times bigger than a grapefruit with a 14 cm diameter.
Q1. About how big would planet Earth be on this scale? [Show size with your hands or an object. <RETURN> for answer.]
Assume the Sun is the size of a large grapefruit:
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!
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.
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!
A. Family of the SunSUMMARY
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:
“Small and Large” “Near and Far”
1. 1.
2. 2.
3. 3.
4. 4.
5. 5.
6. 6.
7. 7.
8. 8.
9. 9.
Smallest
Largest
Closest
Farthest
Two Astronomy Games Copyright 2004 Cherilynn Morrow – Used with permission [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 I. JUPITER
F. BEARS
Press ENTER for a HINT
Mars has no oceans and the sameLAND 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]
7A. THE SUN
5B. EARTH
2C. SPACE SHUTTLE 3D. THE MOON
8E. THE SOLAR SYSTEM
1F. BEARS
4G. MARS 6I. JUPITER
9H. A GALAXY
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]
A. THE SUN B. A GALAXY C. AURORAS
D. THE MOON E. JET AIRPLANE F. HUBBLE TELESCOPE
G. AN EAGLE H. STARS OF THE BIG DIPPER I. SATURN
Auroras occur in Earth’suppermost atmosphere
Stars we see are withinthe Milky Way galaxy
If we see a whole spiral, it can’t be our own galaxy.
Saturn is 10 times fartherfrom the Sun than Earth
The Space Shuttle can visitHubble, but not the Moon
Press ENTER for HINTS
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]
G. AN EAGLE E. JET AIRPLANE C. AURORAS
F. HUBBLE TELESCOPED. THE MOON
A. THE SUN
I. SATURN H. STARS OF THE BIG DIPPER B. A GALAXY
Two Astronomy Games Copyright 2004 Cherilynn Morrow – Used with permission [email protected]
These games are available on-line in multiple modalities:
1. As you see it here in PowerPoint2. As a downloadable card game for the exhibit floor3. As an on-line interactive4. As 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]