Characterizing Stars

Size: px
Start display at page:

Download "Characterizing Stars"

Transcription

1 Characterizing Stars

2 The stars Every star you see in the sky is a large hot ball of gas like our star the Sun. Each one possibly making up a solar system with planets and debris orbiting around them. Stellar parallax can be used to find out how far away a star is from us. The closest star to us is called Proxima Centauri, it is about 25 trillion miles away. Light from this star takes about four years to reach us.

3 Stellar parallax Parallax is the viewing of an object from two different locations. This will cause the object to appear in different places compared to a background. The angle between the two apparent locations is called the parallax angle. The closer the object is the larger the parallax angle will be.

4

5 Calculating distance using parallax The distance from earth to a star can be calculated using the equation: d = 1 p In this equation d is distance in units of parsecs and p is the parallax angle in units of arcseconds. In a circle there is 360 degrees or 24 hours of arc. Each h of arc can be spit into 60 arcminutes, and each m of arc can be split into 60 arcseconds.

6 Example The nearest star to us is observed to have a parallax angle of 0.77 arcsec. How far away is the star in parsecs and light years? (1 pc = 3.26 ly) d = 1 p d = arcsec d = 1.3 pc d = 1.3 pc x 3.26 ly 1 pc = 4.24 ly

7 The brightness of a star In astronomy we refer to a stars brightness as its magnitude. There are two types of magnitudes when it comes to an objects brightness. One is called apparent magnitude and the other absolute magnitude.

8 Apparent magnitude Apparent magnitude denoted by lower case m, is the brightness of a star as seen from Earth. This apparent magnitude doesn't take into account how far away the star is. Therefore apparent magnitude is not the stars actual brightness.

9 Apparent magnitude scale The apparent magnitude scale has positive and negative numbers. The bigger the positive number the dimmer the object. The bigger the negative number the brighter the object.

10

11 Inverse-square law The same amount of radiation must illuminate a larger area as it gets further from the source. This is why an object looks dimmer the further you are from it. Brightness decreases inversely with the square of the distance from the source of light. This is also known as the inverse-square law. I 1 d 2

12 Example You are a certain distance d away from a light source and measure the brightness to be of a certain intensity I. How would the intensity change if you are (a) twice, and (b) half as far from the source?

13 Example continued (a) I 1 d 2 I 1 (2d) 2 I 1 4d 2 Therefore if the distance is doubled the intensity will be one fourth the original, or four times dimer.

14 Example continued (b) I 1 d 2 I 1 ( 1 2 d)2 I d2 = 4 d 2 Therefore if the distance is halved the intensity will be four times the original, or four times as bright.

15 Absolute magnitude Absolute magnitude takes into account that there are different stars at different distances from us. It also uses the same scale as apparent magnitude. If the apparent magnitude and distance of a star is known, that stars absolute magnitude can be calculated. Absolute magnitude (M), is the brightness each star would have at a distance of 10 pc (32.6 ly).

16 Calculating absolute magnitude To calculate absolute magnitude use the equation: M: absolute magnitude M = m 5 log d 10 m: apparent magnitude d: distance in parsecs

17 Example The star Proxima Centauri is 1.3 pc away from Earth and has an apparent magnitude of What is its absolute magnitude? M = m 5 log d 10 M = log M = M = 11.1 ( 4.4) M = +15.5

18 A stars color and temperature A stars color and surface temperature are related. A red stars have the lowest surface temperature, while a blue stars have the highest surface temperature.

19

20 Types of stars Stars come in many different sizes, brightness, and colors. There are four major types of stars. White dwarfs, main sequence stars, giants, and super gaints.

21

Lecture Outlines. Chapter 17. Astronomy Today 8th Edition Chaisson/McMillan Pearson Education, Inc.

Lecture Outlines. Chapter 17. Astronomy Today 8th Edition Chaisson/McMillan Pearson Education, Inc. Lecture Outlines Chapter 17 Astronomy Today 8th Edition Chaisson/McMillan Chapter 17 Measuring the Stars Units of Chapter 17 17.1 The Solar Neighborhood 17.2 Luminosity and Apparent Brightness 17.3 Stellar

More information

Lecture 16 The Measuring the Stars 3/26/2018

Lecture 16 The Measuring the Stars 3/26/2018 Lecture 16 The Measuring the Stars 3/26/2018 Test 2 Results D C B A Questions that I thought were unfair: 13, 18, 25, 76, 77, 80 Curved from 85 to 79 Measuring stars How far away are they? How bright are

More information

Guiding Questions. Measuring Stars

Guiding Questions. Measuring Stars Measuring Stars Guiding Questions 1. How far away are the stars? 2. What is meant by a first-magnitude or second magnitude star? 3. Why are some stars red and others blue? 4. What are the stars made of?

More information

5. A particular star has an angle of parallax of 0.2 arcsecond. What is the distance to this star? A) 50 pc B) 2 pc C) 5 pc D) 0.

5. A particular star has an angle of parallax of 0.2 arcsecond. What is the distance to this star? A) 50 pc B) 2 pc C) 5 pc D) 0. Name: Date: 1. How far away is the nearest star beyond the Sun, in parsecs? A) between 1 and 2 pc B) about 12 pc C) about 4 pc D) between 1/2 and 1 pc 2. Parallax of a nearby star is used to estimate its

More information

Get ready for quiz # 5! Get out a ½ sheet and Calculator

Get ready for quiz # 5! Get out a ½ sheet and Calculator Get ready for quiz # 5! Get out a ½ sheet and Calculator The above image shows the solar eclipse earlier this month as covered and uncovered by several different solar observatories. The innermost image

More information

Stars I. Distance and Magnitude. How Does One Measure Distance? Distances. Stellar Parallax. Distance Equation some examples!

Stars I. Distance and Magnitude. How Does One Measure Distance? Distances. Stellar Parallax. Distance Equation some examples! Stars I Distance and Magnitude Chapter 17 Why doesn t comparison work? Distances The nearest star (Alpha Centauri) is 40 trillion kilometers away(4 ly) Distance is one of the most important quantities

More information

Reading and Announcements. Read Chapters 9.5, 9.6, and 11.4 Quiz #4, Thursday, March 7 Homework #5 due Tuesday, March 19

Reading and Announcements. Read Chapters 9.5, 9.6, and 11.4 Quiz #4, Thursday, March 7 Homework #5 due Tuesday, March 19 Reading and Announcements Read Chapters 9.5, 9.6, and 11.4 Quiz #4, Thursday, March 7 Homework #5 due Tuesday, March 19 Stars The stars are distant and unobtrusive, but bright and enduring as our fairest

More information

a. Star A c. The two stars are the same distance b. Star B d. Not enough information

a. Star A c. The two stars are the same distance b. Star B d. Not enough information Name: Astro 102 S17 Test 1 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. Your test is Version A. Please fill in the circle for A for this question on

More information

Chapter 11 Surveying the Stars

Chapter 11 Surveying the Stars Chapter 11 Surveying the Stars Luminosity Luminosity: Rate of energy emitted by star every second. Apparent brightness (flux): Amount of energy passing through every second per unit area. Luninosity =

More information

Mass-Luminosity and Stellar Lifetimes WS

Mass-Luminosity and Stellar Lifetimes WS Name Mass-Luminosity and Stellar Lifetimes WS The graph shows the Mass-Luminosity Relationship for main sequence stars. Use it to answer questions 1-3. 1) A star with a mass of 0.5 solar masses would be

More information

27.1: Characteristics of Stars

27.1: Characteristics of Stars 27.1: Characteristics of Stars STAR NOTES: Part 1 What is a Star? A body of gases that gives off energy in the form of light and heat. 27.1: Characteristics of Stars Are all stars the same? No 1. Stars

More information

Astronomy. The Nature of Stars

Astronomy. The Nature of Stars Astronomy A. Dayle Hancock adhancock@wm.edu Small 239 Office hours: MTWR 10-11am The Nature of Stars Distances to stars A Star's brightness and Luminosity A Magnitude scale Color indicates a Star's temperature

More information

Astronomy 150: Killer Skies. Lecture 20, March 7

Astronomy 150: Killer Skies. Lecture 20, March 7 Assignments: Astronomy 150: Killer Skies HW6 due next time at start of class Lecture 20, March 7 Office Hours begin after class or by appointment Night Observing continues this week, 7-9 pm last week!

More information

Intro to Astrophysics

Intro to Astrophysics Intro to Astrophysics Dr. Bill Pezzaglia 1 III. Introduction To Astrophysics A. Distances to Stars B. Binary Stars C. HR Diagrams 2 Updated: Nov 2007 A. Stellar Distances 1. Method of Parallax 2. Absolute

More information

Observed Properties of Stars ASTR 2120 Sarazin

Observed Properties of Stars ASTR 2120 Sarazin Observed Properties of Stars ASTR 2120 Sarazin Extrinsic Properties Location Motion kinematics Extrinsic Properties Location Use spherical coordinate system centered on Solar System Two angles (θ,φ) Right

More information

Position 1 Position 2 6 after position 1 Distance between positions 1 and 2 is the Bigger = bigger parallax (Ɵ)

Position 1 Position 2 6 after position 1 Distance between positions 1 and 2 is the Bigger = bigger parallax (Ɵ) STARS CHAPTER 10.1 the solar neighborhood The distances to the nearest stars can be measured using Parallax => the shift of an object relative to some distant background as the observer s point of view

More information

Parallax: Measuring the distance to Stars

Parallax: Measuring the distance to Stars Measuring the Stars Parallax: Measuring the distance to Stars Use Earth s orbit as baseline Parallactic angle = 1/2 angular shift Distance from the Sun required for a star to have a parallactic angle of

More information

Light and Stars ASTR 2110 Sarazin

Light and Stars ASTR 2110 Sarazin Light and Stars ASTR 2110 Sarazin Doppler Effect Frequency and wavelength of light changes if source or observer move Doppler Effect v r dr radial velocity dt > 0 moving apart < 0 moving toward Doppler

More information

Basic Properties of the Stars

Basic Properties of the Stars Basic Properties of the Stars The Sun-centered model of the solar system laid out by Copernicus in De Revolutionibus (1543) made a very specific prediction: that the nearby stars should exhibit parallax

More information

Astronomy Exam 3 - Sun and Stars

Astronomy Exam 3 - Sun and Stars Astronomy Exam 3 - Sun and Stars Study online at quizlet.com/_4zgp6 1. `what are the smallest group of stars in the H-R diagram 2. A star has a parallax of 0.05". what is the distance from the earth? white

More information

PHY2083 ASTRONOMY. Dr. Rubina Kotak Office F016. Dr. Chris Watson Office S036

PHY2083 ASTRONOMY. Dr. Rubina Kotak Office F016. Dr. Chris Watson Office S036 PHY2083 ASTRONOMY Dr. Rubina Kotak r.kotak@qub.ac.uk Office F016 Dr. Chris Watson c.a.watson@qub.ac.uk Office S036 PHY2083 ASTRONOMY Weeks 1-6: Monday 10:00 DBB 0G.005 Wednesday 9:00 PFC 02/018 Friday

More information

Chapter 10 Measuring the Stars

Chapter 10 Measuring the Stars Chapter 10 Measuring the Stars Some of the topics included in this chapter Stellar parallax Distance to the stars Stellar motion Luminosity and apparent brightness of stars The magnitude scale Stellar

More information

Astronomy 122 Outline

Astronomy 122 Outline Astronomy 122 Outline This Class (Lecture 12): Stars Next Class: The Nature of Stars Homework #5 is posted. Nightlabs have started! Stellar properties Parallax (distance) Colors Spectral Classes Music:

More information

Chapter 8: The Family of Stars

Chapter 8: The Family of Stars Chapter 8: The Family of Stars We already know how to determine a star s surface temperature chemical composition motion Next, we will learn how we can determine its distance luminosity radius mass Measuring

More information

Pr P ope p rti t es s of o f St S a t rs

Pr P ope p rti t es s of o f St S a t rs Properties of Stars Distances Parallax ( Triangulation ): - observe object from two separate points - use orbit of the Earth (1 AU) - measure angular shift of object - angle depends on distance to object

More information

Measuring Radial & Tangential Velocity. Radial velocity measurement. Tangential velocity measurement. Measure the star s Doppler shift

Measuring Radial & Tangential Velocity. Radial velocity measurement. Tangential velocity measurement. Measure the star s Doppler shift 17. The Nature of the Stars Parallax reveals stellar distance Stellar distance reveals luminosity Luminosity reveals total energy production The stellar magnitude scale Surface temperature determines stellar

More information

Properties of Stars. 1.1 Brightnesses of Stars

Properties of Stars. 1.1 Brightnesses of Stars Properties of Stars 1.1 Brightnesses of Stars I m sure you have noticed that some stars are very bright, others less bright, and some are quite dim. There is a true brightness of a star and an apparent

More information

The principle of geometrical parallax

The principle of geometrical parallax The principle of geometrical parallax One of the hardest things to do in astronomy is to determine how far away things are. Does the star Vega in Lyra appear exceptionally bright because it s an intrinsically

More information

Distance and Size of a Celestial Body

Distance and Size of a Celestial Body PHYS 320 Lecture 2 Distance and Size of a Celestial Body Jiong Qiu MSU Physics Department Wenda Cao NJIT Physics Department Outline q Lecture 2 Distance and Size of a Celestial Body n n n n n n n n 2.1

More information

Properties of Stars (continued) Some Properties of Stars. What is brightness?

Properties of Stars (continued) Some Properties of Stars. What is brightness? Properties of Stars (continued) Some Properties of Stars Luminosity Temperature of the star s surface Mass Physical size 2 Chemical makeup 3 What is brightness? Apparent brightness is the energy flux (watts/m

More information

Introduction To Modern Astronomy I: Solar System

Introduction To Modern Astronomy I: Solar System ASTR 111 003 Fall 2007 Lecture 01 Aug. 27, 2007 Introduction To Modern Astronomy I: Solar System Introducing Astronomy (chap. 1-6) Planets and Moons (chap. 7-15) Chap. 16: Our Sun Chap. 28: Search for

More information

Chapter 15 Surveying the Stars Pearson Education, Inc.

Chapter 15 Surveying the Stars Pearson Education, Inc. Chapter 15 Surveying the Stars 15.1 Properties of Stars Our goals for learning: How do we measure stellar luminosities? How do we measure stellar temperatures? How do we measure stellar masses? 1. How

More information

15.1 Properties of Stars

15.1 Properties of Stars Surveying the Stars 15.1 Properties of Stars Our goals for learning: How do we measure stellar luminosities? How do we measure stellar temperatures? How do we measure stellar masses? How do we measure

More information

Lecture 12: Distances to stars. Astronomy 111

Lecture 12: Distances to stars. Astronomy 111 Lecture 12: Distances to stars Astronomy 111 Why are distances important? Distances are necessary for estimating: Total energy released by an object (Luminosity) Masses of objects from orbital motions

More information

Astronomy 1143 Quiz 1 Review

Astronomy 1143 Quiz 1 Review Astronomy 1143 Quiz 1 Review Prof. Pradhan September 7, 2017 I What is Science? 1. Explain the difference between astronomy and astrology. Astrology: nonscience using zodiac sign to predict the future/personality

More information

Astronomical Measurements: Brightness-Luminosity-Distance-Radius- Temperature-Mass. Dr. Ugur GUVEN

Astronomical Measurements: Brightness-Luminosity-Distance-Radius- Temperature-Mass. Dr. Ugur GUVEN Astronomical Measurements: Brightness-Luminosity-Distance-Radius- Temperature-Mass Dr. Ugur GUVEN Space Science Distance Definitions One Astronomical Unit (AU), is the distance from the Sun to the Earth.

More information

ASTR-1020: Astronomy II Course Lecture Notes Section III

ASTR-1020: Astronomy II Course Lecture Notes Section III ASTR-1020: Astronomy II Course Lecture Notes Section III Dr. Donald G. Luttermoser East Tennessee State University Edition 4.0 Abstract These class notes are designed for use of the instructor and students

More information

Astronomy 141 Life in the Universe Professor Gaudi Homework #4 Solutions

Astronomy 141 Life in the Universe Professor Gaudi Homework #4 Solutions Astronomy 141 Life in the Universe Autumn Quarter 008 Prof Gaudi Homework #4 Solutions These questions concern the concept of targets for searches for extrasolar planets specifically (a) the number of

More information

INSIDE LAB 8: Plotting Stars on the Hertzsprung- Russell Diagram

INSIDE LAB 8: Plotting Stars on the Hertzsprung- Russell Diagram INSIDE LAB 8: Plotting Stars on the Hertzsprung- Russell Diagram OBJECTIVE: To become familiar with the Hertzsprung-Russell diagram and the method of spectroscopic parallax. DISCUSSION: The Hertzsprung-Russell

More information

= 4,462K T eff (B) =

= 4,462K T eff (B) = Homework 1 Solutions Problem 1: Star A emits most of its light in the orange, Star B in the gre en and Star C in the blue color range. What wavelengths are these most likely to be, and what effective temperature

More information

Lecture 26 The Hertzsprung- Russell Diagram January 13b, 2014

Lecture 26 The Hertzsprung- Russell Diagram January 13b, 2014 1 Lecture 26 The Hertzsprung- Russell Diagram January 13b, 2014 2 Hertzsprung-Russell Diagram Hertzsprung and Russell found a correlation between luminosity and spectral type (temperature) 10000 Hot, bright

More information

Distances to Stars. Important as determines actual brightness but hard to measure as stars are so far away

Distances to Stars. Important as determines actual brightness but hard to measure as stars are so far away SECTION II: Nature of Stars Astronomers measure properties of Stars Distance Mass Apparent Brightness Surface Temperature Radius Find that some are related Large Mass Large Absolute Brightness We will

More information

Life Cycle of a Star - Activities

Life Cycle of a Star - Activities Name: Class Period: Life Cycle of a Star - Activities A STAR IS BORN STAGES COMMON TO ALL STARS All stars start as a nebula. A nebula is a large cloud of gas and dust. Gravity can pull some of the gas

More information

Astronomy-part 3 notes Properties of Stars

Astronomy-part 3 notes Properties of Stars Astronomy-part 3 notes Properties of Stars What are Stars? Hot balls of that shine because nuclear fusion (hydrogen to helium) is happening at their cores. They create their own. Have different which allow

More information

LESSON topic: formation of the solar system Solar system formation Star formation Models of the solar system Planets in our solar system

LESSON topic: formation of the solar system Solar system formation Star formation Models of the solar system Planets in our solar system Unit 2 Lesson 1 LESSON topic: formation of the solar system - Solar system formation - Star formation - Models of the solar system - Planets in our solar system Big bang theory Origin of the universe According

More information

How to Understand Stars Chapter 17 How do stars differ? Is the Sun typical? Location in space. Gaia. How parallax relates to distance

How to Understand Stars Chapter 17 How do stars differ? Is the Sun typical? Location in space. Gaia. How parallax relates to distance How to Understand Stars Chapter 7 How do stars differ? Is the Sun typical? Image of Orion illustrates: The huge number of stars Colors Interstellar gas Location in space Two dimensions are easy measure

More information

Science Period. Astronomy Unit PracticeTest 2014 Sci 7

Science Period. Astronomy Unit PracticeTest 2014 Sci 7 Name: Date: Science Period Astronomy Unit PracticeTest 2014 Sci 7 Directions: Write the letter of the BEST answer on the appropriate space on the answer sheet. 2 points each 1.The model in which SUN is

More information

Stars: Stars and their Properties

Stars: Stars and their Properties Stars: Stars and their Properties Astronomy 110 Class 10 WHEN I heard the learn d astronomer; When the proofs, the figures, were ranged in columns before me; When I was shown the charts and the diagrams,

More information

Phys 100 Astronomy (Dr. Ilias Fernini) Review Questions for Chapter 1

Phys 100 Astronomy (Dr. Ilias Fernini) Review Questions for Chapter 1 Phys 100 Astronomy (Dr. Ilias Fernini) Review Questions for Chapter 1 MULTIPLE CHOICE (Right answers are reported in red) 1.. A solar system contains a. primarily planets. b. large amounts of gas and dust

More information

How does the Sun shine? What is the Sun s structure? Lifetime of the Sun. Luminosity of the Sun. Radiation Zone. Core 3/30/17

How does the Sun shine? What is the Sun s structure? Lifetime of the Sun. Luminosity of the Sun. Radiation Zone. Core 3/30/17 What is the Sun s structure? From inside out, the layers are: Core Radiation Zone Convection Zone Photosphere Chromosphere Corona How does the Sun shine? The Sun has its own energy source Main difference

More information

Review Chapter 10. 2) A parsec is slightly more than 200,000 AU. 2)

Review Chapter 10. 2) A parsec is slightly more than 200,000 AU. 2) Review Chapter 10 TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. 1) A parsec is about 3.3 light-years. 1) 2) A parsec is slightly more than 200,000 AU. 2) 3) The nearest

More information

Stars and Galaxies 1

Stars and Galaxies 1 Stars and Galaxies 1 Characteristics of Stars 2 Star - body of gases that gives off great amounts of radiant energy as light and heat 3 Most stars look white but are actually different colors Antares -

More information

Measuring Distances. Taking the Measure of the Universe

Measuring Distances. Taking the Measure of the Universe Measuring Distances Taking the Measure of the Universe The Importance of Distance We talked about how the brightness of a star can be due to 2 effects: distance or luminosity. Without a direct measurement

More information

Astronomy 113. Dr. Joseph E. Pesce, Ph.D. Dr. Joseph E. Pesce, Ph.D.

Astronomy 113. Dr. Joseph E. Pesce, Ph.D. Dr. Joseph E. Pesce, Ph.D. Astronomy 113 Dr. Joseph E. Pesce, Ph.D. The Nature of Stars 8-2 Parallax For nearby stars - measure distances with parallax July 1 AU d p A A A January ³ d = 1/p (arcsec) [pc] ³ 1pc when p=1arcsec; 1pc=206,265AU=3

More information

Chapter 15: Surveying the Stars

Chapter 15: Surveying the Stars Chapter 15 Lecture Chapter 15: Surveying the Stars Surveying the Stars 15.1 Properties of Stars Our goals for learning: How do we measure stellar luminosities? How do we measure stellar temperatures? How

More information

Astronomy 150 K. Nordsieck Spring Exam 1 Solutions. 1. ( T F ) In Madison the North Star, Polaris, is situated almost exactly at the zenith.

Astronomy 150 K. Nordsieck Spring Exam 1 Solutions. 1. ( T F ) In Madison the North Star, Polaris, is situated almost exactly at the zenith. Astronomy 150 K. Nordsieck Spring 2000 Exam 1 Solutions True or False (Circle T or F) 1. ( T F ) In Madison the North Star, Polaris, is situated almost exactly at the zenith. False. Polaris is near the

More information

Measuring Radial & Tangential Velocity. Radial velocity measurement. Tangential velocity measurement. Measure the star s Doppler shift

Measuring Radial & Tangential Velocity. Radial velocity measurement. Tangential velocity measurement. Measure the star s Doppler shift 17. The Nature of the Stars Parallax reveals stellar distance Stellar distance reveals luminosity Luminosity reveals total energy production The stellar magnitude scale Surface temperature determines stellar

More information

Astronomy 1 Fall 2016

Astronomy 1 Fall 2016 Astronomy 1 Fall 2016 Announcement: Tonight s observing session with Stephanie Ho has been CANCELLED. She has rescheduled it for 8-9pm on Thursday Nov. 3 rd. Hopefully the clouds will part by then. Lecture

More information

AST 301 Introduction to Astronomy

AST 301 Introduction to Astronomy AST 301 Introduction to Astronomy John Lacy RLM 16.332 471-1469 lacy@astro.as.utexas.edu Myoungwon Jeon RLM 16.216 471-0445 myjeon@astro.as.utexas.edu Bohua Li RLM 16.212 471-8443 bohuali@astro.as.utexas.edu

More information

The Cosmic Perspective. Surveying the Properties of Stars. Surveying the Stars. How do we measure stellar luminosities?

The Cosmic Perspective. Surveying the Properties of Stars. Surveying the Stars. How do we measure stellar luminosities? Surveying the Stars Chapter 15 Lecture The Cosmic Perspective 15.1 Properties of Stars Our goals for learning: How do we measure stellar luminosities? How do we measure stellar temperatures? How do we

More information

The Scale of the Cosmos

The Scale of the Cosmos The Scale of the Cosmos Scale defined as relative magnitude. Astronomy deals with objects on a vast range of size scales and time scales. Most of these size and time scales are way beyond our every-day

More information

The Scale of the Cosmos

The Scale of the Cosmos The Scale of the Cosmos Scale defined as relative magnitude. Astronomy deals with objects on a vast range of size scales and time scales. Most of these size and time scales are way beyond our every-day

More information

Universe. Tenth Edition. The Nature of the Stars. Parallax. CHAPTER 17 The Nature of Stars

Universe. Tenth Edition. The Nature of the Stars. Parallax. CHAPTER 17 The Nature of Stars Universe Tenth Edition The Nature of the Stars Roger A. Freedman, Robert M. Geller, William J. Kaufmann III CHAPTER 17 The Nature of Stars W. H. Freeman and Company Parallax Careful measurements of the

More information

Test #2 results. Grades posted in UNM Learn. Along with current grade in the class

Test #2 results. Grades posted in UNM Learn. Along with current grade in the class Test #2 results Grades posted in UNM Learn D C B A Along with current grade in the class F Clicker Question: If the Earth had no Moon then what would happen to the tides? A: The tides would not be as strong

More information

A star is at a distance of 1.3 parsecs, what is its parallax?

A star is at a distance of 1.3 parsecs, what is its parallax? Stars Spectral lines from stars Binaries and the masses of stars Classifying stars: HR diagram Luminosity, radius, and temperature Vogt-Russell theorem Main sequence Evolution on the HR diagram A star

More information

How do we measure properties of a star? Today. Some Clicker Questions - #1. Some Clicker Questions - #1

How do we measure properties of a star? Today. Some Clicker Questions - #1. Some Clicker Questions - #1 Today Announcements: HW#8 due Friday 4/9 at 8:00 am. The size of the Universe (It s expanding!) The Big Bang Video on the Big Bang NOTE: I will take several questions on exam 3 and the final from the videos

More information

IB Physics - Astronomy

IB Physics - Astronomy Solar System Our Solar System has eight planets. The picture below shows their relative sizes, but NOT their relative distances. A planet orbits the sun, and has gravitationally cleared its orbital area

More information

The Cosmological Distance Ladder. It's not perfect, but it works!

The Cosmological Distance Ladder. It's not perfect, but it works! The Cosmological Distance Ladder It's not perfect, but it works! First, we must know how big the Earth is. Next, we must determine the scale of the solar system. Copernicus (1543) correctly determined

More information

Chapter 15 Lecture. The Cosmic Perspective Seventh Edition. Surveying the Stars Pearson Education, Inc.

Chapter 15 Lecture. The Cosmic Perspective Seventh Edition. Surveying the Stars Pearson Education, Inc. Chapter 15 Lecture The Cosmic Perspective Seventh Edition Surveying the Stars 15.1 Properties of Stars Our goals for learning: How do we measure stellar luminosities? How do we measure stellar temperatures?

More information

ASTRONOMY QUIZ NUMBER 11

ASTRONOMY QUIZ NUMBER 11 ASTRONOMY QUIZ NUMBER. Suppose you measure the parallax of a star and find 0. arsecond. The distance to this star is A) 0 light-years B) 0 parsecs C) 0. light-year D) 0. parsec 2. A star is moving toward

More information

How big is the Universe and where are we in it?

How big is the Universe and where are we in it? Announcements Results of clicker questions from Monday are on ICON. First homework is graded on ICON. Next homework due one minute before midnight on Tuesday, September 6. Labs start this week. All lab

More information

Modern Astronomy Review #1

Modern Astronomy Review #1 Modern Astronomy Review #1 1. The red-shift of light from distant galaxies provides evidence that the universe is (1) shrinking, only (3) shrinking and expanding in a cyclic pattern (2) expanding, only

More information

Vocabulary. Section Resources

Vocabulary. Section Resources Section 26.2 26.2 Stars 1 FOCUS Objectives 26.2.1 Demonstrate how distance to a star is measured. 26.2.2 Classify stars according to chemical and physical properties. 26.2.3 Interpret the H-R diagram.

More information

Astronomy 210 Spring 2017: Quiz 5 Question Packet 1. can: 2. An electron moving between energy levels

Astronomy 210 Spring 2017: Quiz 5 Question Packet 1. can: 2. An electron moving between energy levels Permitted energy levels Astronomy 210 Spring 2017: Quiz 5 Question Packet 1 1. An electron in energy level 1 2 can: (A) only emit a photon. (B) only absorb a photon. (C) either emit, or absorb a photon.

More information

Earth in Space. Stars, Galaxies, and the Universe

Earth in Space. Stars, Galaxies, and the Universe Earth in Space Stars, Galaxies, and the Universe Key Concepts What are stars? How does the Sun compare to other stars? Where is Earth located in the universe? How is the universe structured? What do you

More information

λ = 650 nm = c = m s 1 f =? c = fλ f = c λ = ( m s 1 ) ( m) = = Hz T = 1 f 4.

λ = 650 nm = c = m s 1 f =? c = fλ f = c λ = ( m s 1 ) ( m) = = Hz T = 1 f 4. Chapter 13 Stars Section 13.1 Astronomical measurements Worked example: Try yourself 13.1.1 CALCULATING THE FREQUENCY AND PERIOD OF LIGHT The speed of light in a vacuum is approximately 3.0 10 8 m s 1.

More information

10/20/2009. Giants, Dwarfs, and the Main Sequences. My Office Hours: Tuesday 3:30 PM - 4:30 PM 206 Keen Building. The Sun and the Stars

10/20/2009. Giants, Dwarfs, and the Main Sequences. My Office Hours: Tuesday 3:30 PM - 4:30 PM 206 Keen Building. The Sun and the Stars the The Sun and the Giants, Dwarfs, and the Main Sequences 10/20/2009 My Office Hours: Tuesday 3:30 PM - 4:30 PM 206 Keen Building the Outline 1 2 3 the Outline 1 2 3 the Solar Structure Interior structure

More information

How do we know the distance to these stars? The Ping Pong Ball Challenge -Devise a method for determining the height of the ping pong ball above the floor. -You are restricted to the floor. -You can only

More information

Answer Key Testname: MT S

Answer Key Testname: MT S Answer Key Testname: MT1-333-12S 1) B 2) A 3) E 4) C 5) C 6) C 7) C 8) A 9) E 10) C 11) A 12) C 13) C 14) C 15) C 16) D 17) A 18) D 19) A 20) C 21) B 22) A 23) A 24) C 25) B 26) C 27) A star with apparent

More information

Stars: basic observations

Stars: basic observations Stars: basic observations Basic properties of stars we would like to know in order to compare theory against observations: Stellar mass M Stellar radius R Surface temperature - effective temperature T

More information

Chapter 15 Surveying the Stars Properties of Stars

Chapter 15 Surveying the Stars Properties of Stars Chapter 15 Surveying the Stars 15.1 Properties of Stars Our goals for learning: How do we measure stellar luminosities? How do we measure stellar temperatures? How do we measure stellar masses? Luminosity:

More information

Astronomy 111. Dr. Joseph E. Pesce, Ph.D. Introduction. Introduction 8/28/14. Astronomy & Astrophysics. Our understanding is based on laws of physics:

Astronomy 111. Dr. Joseph E. Pesce, Ph.D. Introduction. Introduction 8/28/14. Astronomy & Astrophysics. Our understanding is based on laws of physics: 8/28/14 Astronomy 111 Dr. Joseph E. Pesce, Ph.D. 1-4 Introduction Astronomy & Astrophysics Introduction ASTRON = Star NOMOS = Law PHYSIC = Nature 1-5 ³ Astronomy: observable properties of objects in the

More information

Physics Lab #10:! Stellar Parallax!

Physics Lab #10:! Stellar Parallax! opposite Physics 10293 Lab #10: Stellar Parallax Introduction Parallax is a distance determination technique that uses geometry to measure the distance to some object when other means (such as a ruler

More information

Chapter 15 Surveying the Stars

Chapter 15 Surveying the Stars Chapter 15 Surveying the Stars 15.1 Properties of Stars Our goals for learning How do we measure stellar luminosities? How do we measure stellar temperatures? How do we measure stellar masses? How do we

More information

Astronomy, Astrophysics, and Cosmology

Astronomy, Astrophysics, and Cosmology Astronomy, Astrophysics, and Cosmology Luis A. Anchordoqui Department of Physics and Astronomy Lehman College, City University of New York Lesson I February 2, 2016 arxiv:0706.1988 L. A. Anchordoqui (CUNY)

More information

Stellar Composition. How do we determine what a star is made of?

Stellar Composition. How do we determine what a star is made of? Stars Essential Questions What are stars? What is the apparent visual magnitude of a star? How do we locate stars? How are star classified? How has the telescope changed our understanding of stars? What

More information

PH104 Lab 2 Measuring Distances Pre-Lab

PH104 Lab 2 Measuring Distances Pre-Lab Name: Lab Time: PH04 Lab 2 Measuring Distances Pre-Lab 2. Goals This is the second lab. Like the first lab this lab does not seem to be part of a complete sequence of the study of astronomy, but it will

More information

ASTRO 1050 LAB #1: Scientific Notation, Scale Models, and Calculations

ASTRO 1050 LAB #1: Scientific Notation, Scale Models, and Calculations ASTRO 1050 LAB #1: Scientific Notation, Scale Models, and Calculations ABSTRACT We will be doing some review of Math concepts in this lab. Scientific notation, unit conversions, scale modeling, time to

More information

GALAXIES AND STARS. 2. Which star has a higher luminosity and a lower temperature than the Sun? A Rigel B Barnard s Star C Alpha Centauri D Aldebaran

GALAXIES AND STARS. 2. Which star has a higher luminosity and a lower temperature than the Sun? A Rigel B Barnard s Star C Alpha Centauri D Aldebaran GALAXIES AND STARS 1. Compared with our Sun, the star Betelgeuse is A smaller, hotter, and less luminous B smaller, cooler, and more luminous C larger, hotter, and less luminous D larger, cooler, and more

More information

1 (a) Explain what is meant by a white dwarf when describing the evolution of a star [1]

1 (a) Explain what is meant by a white dwarf when describing the evolution of a star [1] 1 (a) Explain what is meant by a white dwarf when describing the evolution of a star.... [1] (b) Antares is a red giant and one of the brightest stars in the night sky. The parallax angle for this star

More information

Chapter 9: Measuring the Stars

Chapter 9: Measuring the Stars Chapter 9: Measuring the Stars About 10 11 (100,000,000,000) stars in a galaxy; also about 10 11 galaxies in the universe Stars have various major characteristics, the majority of which fall into several

More information

Stars, Galaxies & the Universe Announcements. Stars, Galaxies & the Universe Observing Highlights. Stars, Galaxies & the Universe Lecture Outline

Stars, Galaxies & the Universe Announcements. Stars, Galaxies & the Universe Observing Highlights. Stars, Galaxies & the Universe Lecture Outline Stars, Galaxies & the Universe Announcements HW#3 due Tuesday (Tomorrow) at 3 pm Lab Observing Trip Tues (9/28) & Thurs (9/30) First Exam next Wed. (9/22) in class - will post review sheet, practice exam

More information

ClassAction: Stellar Properties Module Instructor s Manual

ClassAction: Stellar Properties Module Instructor s Manual ClassAction: Stellar Properties Module Instructor s Manual Table of Contents Section 1: Warm-up Questions...3 Temperature and Color.....4 Section 2: General Questions.....5 Apparent Magnitude and Brightness....6

More information

Star Magnitudes & Distances with Stellarium (Stellarium Exercise #2)

Star Magnitudes & Distances with Stellarium (Stellarium Exercise #2) Name Date Star Magnitudes & Distances with Stellarium (Stellarium Exercise #2) Millions of stars are scattered across the sky. Astronomers want to study these stars as carefully as possible. This means

More information

The Distance Modulus. Absolute Magnitude. Chapter 9. Family of the Stars

The Distance Modulus. Absolute Magnitude. Chapter 9. Family of the Stars Foundations of Astronomy 13e Seeds Phys1403 Introductory Astronomy Instructor: Dr. Goderya Chapter 9 Family of the Stars Cengage Learning 016 Topics for Today s Class 1. Recap: Intrinsic Brightness a)

More information

Chapter 15 Surveying the Stars. Properties of Stars. Parallax and Distance. Distances Luminosities Temperatures Radii Masses

Chapter 15 Surveying the Stars. Properties of Stars. Parallax and Distance. Distances Luminosities Temperatures Radii Masses hapter 15 Surveying the Stars Properties of Stars istances Luminosities s Radii Masses istance Use radar in Solar System, but stars are so far we use parallax: apparent shift of a nearby object against

More information

1. Basic Properties of Stars

1. Basic Properties of Stars 1. Basic Properties of Stars This is the Sun during a total eclipse. The Sun, our closest star, is very much representative of the objects that we will study during this module, namely stars. Much of the

More information

Surveying the Milky Way

Surveying the Milky Way Surveying the Milky Way How Astronomers Prepared a Detailed Map of the Nearby Regions of Space By the 1920 s Primary References: Astronomy:The Evolving Universe, Michael Zeilik, Second Edition, Harper

More information

AST 301: What you will have to learn and get used to 1. Basic types of objects in the universe

AST 301: What you will have to learn and get used to 1. Basic types of objects in the universe AST 301: What you will have to learn and get used to 1. Basic types of objects in the universe Planets, stars, galaxies, a few things inbetween--look through your textbook soon! You will have to learn:

More information

Measuring the Properties of Stars (ch. 17) [Material in smaller font on this page will not be present on the exam]

Measuring the Properties of Stars (ch. 17) [Material in smaller font on this page will not be present on the exam] Measuring the Properties of Stars (ch. 17) [Material in smaller font on this page will not be present on the exam] Although we can be certain that other stars are as complex as the Sun, we will try to

More information