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

Desc. Astronomy Week 1 Notes

by: Lauren Zerr

Desc. Astronomy Week 1 Notes PHYS 309

Marketplace > Fort Hays State University > Physics 2 > PHYS 309 > Desc Astronomy Week 1 Notes
Lauren Zerr
GPA 3.84
View Full Document for 0 Karma

View Full Document


Unlock These Notes for FREE

Enter your email below and we will instantly email you these Notes for Descriptive Astronomy

(Limited time offer)

Unlock Notes

Already have a StudySoup account? Login here

Unlock FREE Class Notes

Enter your email below to receive Descriptive Astronomy notes

Everyone needs better class notes. Enter your email and we will send you notes for this class for free.

Unlock FREE notes

About this Document

Notes taken in class and during the reading.
Descriptive Astronomy
Kayvan Aflatooni
Class Notes




Popular in Descriptive Astronomy

Popular in Physics 2

This 7 page Class Notes was uploaded by Lauren Zerr on Saturday January 23, 2016. The Class Notes belongs to PHYS 309 at Fort Hays State University taught by Kayvan Aflatooni in Spring 2016. Since its upload, it has received 24 views. For similar materials see Descriptive Astronomy in Physics 2 at Fort Hays State University.


Reviews for Desc. Astronomy Week 1 Notes


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: 01/23/16
Reading Notes - Chapter 1 Thursday, January 21, 2016 9:08 PM All scientific methods used multifaceted observations to pursue consistent evidence when trying to answer questions about the natural world. All scientific investigations are centered on pursuing a question or an unexpected observation, but they do not necessarily test a hypothesis. A hypothesis is traditionally defined as a collection of softly propose mechanism for how the world operates or a comprehensive and complete explanation for why particular observations are seen. The universe is comprehensible. The most widely excepted scientific theories or ones that make accurate predictions that can be independently tested by other scientists. A body of related observations can be pieced together into a comprehensive self-consistent explanatory description of nature called a Theory. Extraordinary claims require extraordinary evidence Huge cloud of interstellar gas, called nebula, are scattered across the sky. Stars are born from the material of the nebula itself. Some stars that are far more massive than the sun end of their lives with the spectacular denotation called a supernova the closest are apart, forming new nebula. The most massive stars in their lives as almost inconceivably dense objects call black holes, who's gravity is so powerful that nothing, not even light, can escape. Galaxies can be called huge assemblages. Asterism are figures created by connecting stars from dot to dot. We can think of Three Stages in this voyage: from earth to the solar system, from the solar system to the stars, and from the stars to the galaxies in the grand scheme of the universe. The nearest star to earth is the sun. For companies that you can buy stars: The money that they charge you for the service is real but the star names are not; none of these names is recognized by professional astronomers. Semi rectangular regions are called constellations. If you live in the southern hemisphere, you can see constellations that are not visible from the northern hemisphere, and vice versa. The you winter triangle, which connects bright stars in the consolations of you of Orion the Canis major in the Canis minor. The summer triangle connects the brightest stars in lyra, Cygnus, and Aquila. Why does the sky go through this daily motion? Why do the constellations slowly ships from one night to the next? As we will see, the answer to the first question is that the earth spins once a day around an axis from the north pole to the South Pole, while the answer to the second question is that earth also Orbits once a year around the sun. The apparent changing sky over the course of the night is due to earth spin, not the rest of the universe moving around a stationary earth. If you follow a particular star on successive evenings, you will find that it rises approximately four minutes earlier each night, or two hours earlier each month. Ancient sky watchers often imagine the stars to be bits of fire in bedded into the inner surface of an immerse hollow sphere, call the Celestial sphere, with earths at it center, and all the stars the same distance from earth. The point in the sky directly overhead and observer anywhere on earth is called the observers zenith. Stars sufficiently near the celestial pole revolve around the polo, never rising or setting. Such stars are called circumpolar. The celestial sphere is an imaginary object that has no basis in physical activity. The celestial equator divided the sky into northern and southern hemispheres, just as earth's equator divide earth into two hemispheres. We obtain points in the sky called the north celestial pole and the south celestial pole. Polaris is also known as the north star because it's almost precisely about earth's north pole. Objects close to the south celestial pole are circumpolar, that is, they revolve around that pole and never rise or set. For an observer in the southern hemisphere, stars close to the north celestial pole are always below the horizon and can never be seen. An angle is the opening between two lines that meet at a point. The basic unit for angles is degrees. The circular path that the sun appears to trace out against the background of stars over the course of a year is called the elliptic. Summer is hot not only because of the extended daylight hours but also because the sun is high in the northern hemispheres sky. When the sun is low in the sky, sunlight strikes the surface at a grazing angle that causes little heating, and it is winter in the southern hemisphere . If the seasons were really caused by variations in the earth-sun distance, the seasons would be the same in both hemispheres. The ecliptic and the celestial equator interesecet at only two points. Each point is called an equinox. The march equinox marks the beginning of spring in the northern hemisphere. The sun is the farthest south of the celestial equator at a point called the southern solstice. One the first day of spring or the first day of autumn when the sun is at one of the equinoxes the sun rises directly in the east and sets directly in the west. The circle around earth at 66 1/2 north latitude is called the arctic circle. The corresponding region around the south pole is bounded by the Antarctic circle at 66 1/2 south latitude. The point on the ecliptic farthest north of the celestial equator is called the northern solstice. These different appearance of the moon are called lunar phases. The light we see on the moon is reflected light. Reflection - the term refers to light bouncing off any object. Moonrise is around midnight and moonset is around noon. The moon takes about four weeks to complete one orbit around earth, so it likewise takes about four weeks for a complete cycle of phases from new moon to full moon and back to new moon. Phases are simply the result of our seeing the illuminated half of the moon at different angles as the moon moves around its orbit. The side of the moon that constantly faces away from earth is properly called the far side. Sidereal month is the time it takes the moon to complete one full orbit of earth, as measured with respect to the stars. Synodic moth, or lunar month, is the time it takes the moon to compete one cycle of phases, and thus is measure with respect to the sun rather than the stars. It takes exactly as long to rotate on its axis as it does to make one orbit around earth. the situation is called synchronous rotation. The lunar eclipse occurs when the moon passes through earth's shadow. The solar eclipse occurs when earth passes through eh moon's shadow. The line of nodes passes through earth and is pointed in a particular direction in space Anyone who wants to predict eclipses must know the orientation of the line of nodes. Totality - the period when the moon is completely within earth's shadow. Umbra - the darkest part of the shadow. When the moon passes through earths' penumbra we see a penumbra ellipse. If the moon travels complete into the umbra, a total lunar eclipse occurs. If only part of the moon passes through the umbra, we see a partial lunar eclipse. Moon just fits over the sun during a total solar eclipse. Perigee - the point in its orbit nearest earth. Apogee - the fathers positon from earth Week 1 Notes Saturday, January 23, 2016 9:52 AM Personal Questions : Who said the earth is at the center and all planets revolve around us? Plato, Aristotle, Ptolemy (geocentric) Who said the earth is not at the center, but revolves around the sun? Nicolaus Copernicus, Aristarchus of Somos (heliocentric) Asterism- many mistake for constellations. 88 constellation cover all the sky. Within the constellation, there are connected dots. Temperature can be associated with star color. Think of a Bunsen burner. Orange/Red - low heat. Blue/White - high heat. Within a second, the sun generates more energy than all electro power plants in 1/2 million years. The sun is converting matter to energy (also true for all stars). The sun converts several millions tons of matter in seconds. In 10 billion years, the sun uses 1/100 of a percent of its own mass. How do we know the Earth spins on its own axis? Days/Nights. The distance in the elliptical orbit to the sun does not cause seasons. Seasons are caused by light due to the 23.5 degree tilt on the axis.


Buy Material

Are you sure you want to buy this material for

0 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

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!"

Amaris Trozzo George Washington University

"I made $350 in just two days after posting 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!"


"Their 'Elite Notetakers' are making over $1,200/month in sales by creating high quality content that helps their classmates in a time of need."

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.