1. The Universe

2. What is your Cosmic Address?
Science Starter
What is your Cosmic Address?
# Street
City
State
Country
Continent
Hemisphere
Planet
Orbit
Star? …? …

3. Review from last class The Universe’s Origin The Universe’s End
Big Bang Theory
Steady State Theory
The Universe’s End
Big Crunch
Expansion Forever

4. Standard 1.1 Structure of the Universe
Objective
SWBAT Distinguish the hierarchical relationships between planets and other astronomical bodies relative to solar system, galaxy, and universe, including distance, size, and composition.
Copyright © Houghton Mifflin Harcourt Publishing Company

5. Agenda Science Starter Into to the Universe size & Scale
Practice time!

6. Remember our Lesson Goal!
1. What makes up the universe?
By the end of this lesson, you should be able to describe the structure of the universe, including the scale of distance in the universe.

7. How Big Is Big? How are distances in the universe measured?
Standard 1.1 Structure of the Universe
How Big Is Big?
How are distances in the universe measured?
Distances between most objects in the universe are so large that astronomers measure distances using the speed of light.
A light-year is the distance that light travels through space in one year.

8. Size and Scale of the Universe
Realms of the Universe
Image courtesy of The Cosmic Perspective by Bennett, Donahue, Schneider, & Voit; Addison Wesley, 2002

10. EARTH Comprised primarily of rock
Earth is one of eight planets that orbit the sun
12,700 km in diameter
It would take 17 days to circumnavigate the globe driving a car at 100 km/hr (62 mph)
Image Credit: NASA/JPL/GSFC

11. sun The star that Earth orbits
Uses nuclear fusion in its core to generate heat and light to allow itself to resist the crushing weight of its own mass
Image Credit: SOHO/NASA/ESA

12. Sun & Earth The Sun’s diameter is 109 times greater than that of Earth
Over 1 million Earths would fit inside
It would take 11,780 Earths lined up side to side to bridge the gap between Earth and Sun
Sun & Earth
Image Credit: SOHO/NASA/ESA

13. Size and Scale of the Universe
The Solar system
Consists of:
1 large object
Sun
several medium-sized objects
8 planets, some dwarf planets, and moons
lots of debris
asteroids, meteoroids, comets, dust
Image credit: NASA
Image credit: NASA

14. Size and Scale of the Universe
The Solar system
A planet is a spherical body that orbits the sun. The sun is our central star.
Moons are smaller bodies that orbit most planets.
A star is a large celestial body that is composed of gas and emits light.
Asteroids: Rocky and metallic objects too small to be considered planets.
Meteorites are bits of the solar system that have fallen to the Earth.
Comets: small bodies made out of dust and ices
Image credit: NASA
Image credit: NASA

15. The Solar Neighborhood
Size and Scale of the Universe
The Solar Neighborhood
The region of the Galaxy within about 20 light-years of the Sun (40 light-years diameter)
A light-year is the distance that light travels in one year (~10 trillion kilometers or 63,000 AU)
Image credit: Andrew Colvin

16. The Milky Way Galaxy
A galaxy is a large collection of stars, gas, and dust held together by gravity.
The Milky Way Galaxy is a giant disk of stars 100,000 light-years across and 1,000 light-years thick
It takes about 250 million years for the Sun to complete one orbit
There are over 200 billion stars in the Milky Way
Image credit: R. Hurt (SSC), JPL-Caltech, NASA

17. The Local Group (of galaxies)
Size and Scale of the Universe
The Local Group (of galaxies)
About 6.5 million light-years in diameter
Contains 3 large spiral galaxies -- Milky Way, Andromeda(M31), and Triangulum(M33)
Image Credit: Andrew Colvin

18. The Local Supercluster
Size and Scale of the Universe
The Local Supercluster
The Local Supercluster is about 130 million light-years across
It’s a huge cluster of thousands upon thousands of galaxies
Containing well over a thousand galaxies
Image credit: Andrew Colvin

19. The Supercluster Earth Belong To:

20. The Universe (the observable portion)
Size and Scale of the Universe
The Universe (the observable portion)
Probably at least 100 billion galaxies in the Universe
The Observable Universe is currently about 91 billion light-years across
There could be (and likely is) much more beyond that, but we cannot see it from
The universe can be defined as space and all the matter and energy in it.

21. What is the structure of the universe?
Standard 1.1 Structure of the Universe
What is the structure of the universe?
Astronomers have begun to think of the universe as having a structure similar to soap bubbles.
Clusters and superclusters are located along the thin bubble walls.
The interior of the bubbles are voids. It takes light hundreds of millions of years to cross the largest voids.

22. Using the table below, construct your own diagram of the universe
Realm
Actual Size
(diameter in km)
Scale Model
Earth
12,700 (1.27E+4)
salt grain (0.1 mm)
Sun
1.39 million (1.39E+6)
gum ball (1.09 cm)
Solar System
30 billion (3.0E+10)
football stadium (234 meters)
Solar Neighborhood
378 trillion (3.78E+14)
~ size of Moon (3,480 km)
Galaxy
946 quadrillion (9.46E+17)
5.4 Suns (7.5 million km)
Local Group
(of galaxies)
62 quintillion (6.15E+19)
orbit of Mars
-diameter (~3 AU)
Local Supercluster
1.2 sextillion (1.2E+21)
orbit of Neptune
-diameter (~60 AU)
Universe
860.9 sextillion (8.6E+23)
Oort Cloud-radius (48,000 AU or 0.76 ly)
Be sure to include things like asteroids, other planets, etc
Using what you know, write two paragraphs explaining Earth’s location in the universe.