New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here

Astronomy 101

by: Glaiza Julian
Glaiza Julian
Cal State Fullerton

Ben Jose

Almost Ready


These notes were just uploaded, and will be ready to view shortly.

Purchase these notes here, or revisit this page.

Either way, we'll remind you when they're ready :)

Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

Chapter 1 textbook notes for "The Essential Cosmic Perspective", 7th edition. This chapter is called "A Modern View of the Universe" and has three sections: The Scale of the Universe, The History o...
Ben Jose
One Day of Notes
Astronomy 101
25 ?




Popular in Course

Popular in Physics 2

This 8 page One Day of Notes was uploaded by Glaiza Julian on Friday August 29, 2014. The One Day of Notes belongs to a course at California State University - Fullerton taught by a professor in Fall. Since its upload, it has received 155 views.

Similar to Course at Cal State Fullerton


Reviews for Astronomy 101


Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 08/29/14
Chapter 1 A Modern View of The Universe Reading Notes 11 The Scale of the Universe What is our place in the universe Our Cosmic Address Solar System or star system A star sometimes more than one star and all the objects that orbit it Earth is a planet in our solar system the solar system is comprised of the Sun the planets and their moons and a myriad of smaller objects including rocky asteroids and icy comets Milky Way Galaxy Used both as the name of our galaxy and to refer to the band of light we see in the sky when we look into the plane of the Milky Way Galaxy Mix A great island of stars in space containing millions billions or even trillions of stars all held together by gravity and orbiting a common center Our solar system is a little over 12 way from the galactic center to the edge of the galactic disk Galaxies are fairly isolated but many are found in groups Local Group The group of about 40 galaxies to which the Milky Way belongs to The Milky Way is one of two of the largest galaxies in the Local Group Galaxy Clusters Groups of galaxies with more than a few dozen large members Superclusters The largest known structures in the universe consisting of many clusters of galaxies group of galaxies and individual galaxies The Local Group is located in the outskirts of the Local Supercluster Universe The sum total of all matter and energy Astronomical Distance Measurements Astronomical Unit AU Earth s average distance from the Sun which is about 150 million kilometers 93 million miles Distances within our solar system are commonly described in astronomical units Light Year y The distance that light can travel in 1 year which is about 10 trillion kilometers 6 trillion miles Light years are generally used to describe the distance of stars and galaxies A light year is a unit of distance not time Light travels at the speed of light which is about 300000 km second Looking Back in Time Stars are so far in distance that their light takes years to reach us Thus why we refer to the distance as a light year The father away we look in distance the further back we look in time For example the brightest star in the night sky Sirius is about 8 light years away which means that when we look at Sirius we are seeing it not as it is today but as it was 8 years ago The Observable Universe Astronomers have measured the age of the universe to be about 14 billion years If we attempted to see past 14 billion light years away which was before the universe existed there would be nothing to see because that would mark the boundary or horizon of our observable universe Observable Universe The portion of the entire universe that at least in principle can be seen from Earth How big is the universe The Scale of the Solar System Sun grapefruit Jupiter the size of a marble Earth the ballpoint on a pen The storm on Jupiter known as the Great Red Spot could swallow up the entire earth Distance to the Stars The vast distances to the stars offer a sobering lesson about interstellar travel If you were visiting the Voyage model in Washington DC you could walk the approximate 600 meter distance from the Sun to Pluto in a few minutes However the distance to reach the next star on this scale would be equivalent to walking to California from Washington DC The Size of the Milky Way Galaxy Visualize it as the 100000 light year diameter of the Milky Way Galaxy becomes about the length of a football field Our entire solar system is a microscopic dot located around the 20yard line The Observable Universe Imagine this roughly speaking there are as many stars in the observable universe as there are grains of sand on all the beaches of the Earth 12 The History of the Universe Telescopes could act as time machines enabling us to observe the history of the universe How did we come to be The Big Bang Expansion and the Age of the Universe Telescopic observations of distant galaxies illustrate that the entire universe is expanding You can imply that the galaxies must have been closer together before and if you go back far enough you can see the point in which the expansion began BIG BANG Big Bang The name given to the event thought to mark the birth of the universe The universe collectively may be expanding but smaller size scales show that the force of gravity has drawn matter together For instance structures such as galaxies and galaxy clusters occupy regions where gravity has prevailed against overall expansion Stellar Lives and Galactic Recycling Within galaxies gravity drives the collapse of clouds of gas and dust to form stars and planets A star is born when gravity compresses the material in a cloud to the point at which the center becomes dense enough and hot enough to generate energy by nuclear fusion Nuclear Fusion The process in which two or more nuclei slam together and make one larger nucleus The star lives as long as it can generate energy from fusion and dies when it exhausts its usable fuel Star Stuff The most massive stars die in titanic explosions called supernovae The returned matter mixes in with other matter owing between the stars in the galaxy eventually becoming part of new clouds of gas and dust from which future generations of stars can be born Galaxies cosmic recycling plants Elements comprising humans and earth are primarily made of other elements carbon nitrogen etc that were manufactured by stars Carl Sagan once said we are star stuff How do our lives compare to the age of the universe 13 Spaceship Earth How is Earth moving through space Rotation and Orbit The most basic motions of Earth are its daily rotations and its yearly orbit or revolution around the Sun Rotation The spinning of an object around its axis 0 The path followed by a celestial body because of gravity an orbit may be bound or elliptical or unbound parabolic or hyperbolic The earth rotates from west to east1 which means counterclockwise as viewed from above the North Pole 1 Which is why the Sun and stars appear to rise in the east and set in the west each day Unless you live a far way up north or south you are whirling around Earth s axis at a speed of more than 1000 kmhr 600 miles per hour The average Earth Sun distance is 1 AU or about 150 million km Earth s axis remains pointed in the same direction toward Polaris throughout the year Earth takes 1 year to orbit the sun at an average speed of 107000 kmhr Earth s orbital path defines a at plane that we call the ecliptic plane Ecliptic Plane The plane of Earth s orbit around the sun Earth s axis is tilted by 23 12 from a line perpendicular to the ecliptic plane Axis Tilt The amount by which a planet s axis is tilted with respect to a line perpendicular to the ecliptic plane Motion Within the Milky Way Galaxy Our solar system is moving relative to nearby stars in our local solar neighborhood the region of the sun and nearby stars Our solar system located about 27000 light years from the galactic center completes one orbit of the galaxy in about 230 million years Movement is rapid but we are unable to see such movement in the sky because of the distance How do galaxies move within the universe The Raisin Cake Analogy Distant galaxies are all moving way from us with more distant ones moving faster indicating that we live in an expanding universe 3010 baking vmewn are 3 39 Clquot azzart L 8 Hamr from n mud pwsnetsir he cut umnm uvdannyu ransahn are dl 3amp1quot Rf ltquot Hanan awtraw he Bavnc u39vwafm lMa39RIan1 awamu nvsm mow tbn uuawawhvug Mixvu w mnavv due1 rauima cmmp ham Drstancas and Speeds as seen row the Local Raisin Rulin oismnce atfore Distance Amer cairn speed kumbet Baking 1 hour later 1 1 cm 3 cm 2 cmN 2 2 cm 6 cm I cmtr 3 3 cm 9 cm 6 cmrr 39 FIGURE 115 IKMAI mnsnacnvs nouns A vxuandrg 39acsIr cake 03955 an anatogy to the uxpardng unrcr5eSo11eorvImrgnr owe at Me 39aar5u3919de1hc cake couc gum o t that the calm 5 cxmrdrug bi rdorg that al nthar vacant Iva nwrung zany with m ave ctmant raxsana rnomng away 155go M are same way we ltvow that we he m an cacnard rq 39mer4 because al aalates octane oJr Loca Grtun are maurg znrcw trcrn us wth more dustaht cncs masrg tastor page 18 Figure 115 The Real Universe Difference between raisin cake and universe a cake has a center and edges but We re not sure if the same is true for the entire universe Distances are too vast within the galaxy and beyond for any motion to be noticeable Motion Summary We are never truly sitting still we spin around Earth s axis at more than 1000 kmhr while our planet orbits the sun at more than 100000 kmhr Our solar system moves among the stars of the local solar neighborhood at typical speeds of 70000 kmhr while also orbiting the center of the Milky Way Galaxy at a speed of about 800000 kmhr


Buy Material

Are you sure you want to buy this material for

25 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."

Kyle Maynard Purdue

"When you're taking detailed notes and trying to help everyone else out in the class, it really helps you learn and understand the I made $280 on my first study guide!"

Bentley McCaw University of Florida

"I was shooting for a perfect 4.0 GPA this semester. Having StudySoup as a study aid was critical to helping me achieve my goal...and I nailed it!"

Parker Thompson 500 Startups

"It's a great way for students to improve their educational experience and it seemed like a product that everybody wants, so all the people participating are winning."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.