Announcements Third exam is Friday, October 29

Slides:

Advertisements

Similar presentations

MEASURING DISTANCES IN ASTRONOMY Basic Principles: Geometric methods Standard candles Standard rulers [the last two methods relate quantities that are.

Advertisements

M09/4/PHYSI/SP3/ENG/TZ1/XX+

How Far is far ? Measuring the size of the Universe.

Astronomical Distances Distances in astronomy are huge The Moon is 240,000 miles away The Sun is 93, 000,000 miles away Neptune is 2,810,687,500 miles.

Announcements Pick up graded tests Homework 12 due today Pick up Homework 13 Second project is due a week from Friday If you’re following our syllabus,

Charles Hakes Fort Lewis College1. Charles Hakes Fort Lewis College2.

The Distance Scale Ladder A Nested Chain of Cumulative Uncertainty.

Measuring the Stars (Part III). The “Cosmic Distance Ladder”

Agenda Read Unit 8 Distance to galaxies (review) Redshift Hubble’s Law The Big Bang.

The extragalactic universe and distance measurements Discovery of the extragalactic universe The cosmic distance ladder.

Structure of the Universe Astronomy 315 Professor Lee Carkner Lecture 21 “The Universe -- Size: Bigger than the biggest thing ever and then some. Much.

Structure of the Universe Astronomy 315 Professor Lee Carkner Lecture 23.

Universe Eighth Edition Universe Roger A. Freedman William J. Kaufmann III CHAPTER 24 Galaxies Galaxies.

GALAXIES, GALAXIES, GALAXIES! A dime a dozen… just one of a 100,000,000,000! 1.Galaxy Classification Ellipticals Dwarf Ellipticals Spirals Barred Spirals.

22 March 2005AST 2010: Chapter 18 1 Celestial Distances.

Distances. Parallax Near objects appear to move more than far objects against a distant horizon. Trigonometric parallax is used to measure distance to.

Galaxies How big is the Universe? Types of galaxies Elliptical Spiral

Measuring Distances. Introduction Trigonometric Parallax Spectroscopic Parallax Cepheid Variables Type Ia Supernovae Tully-Fisher Relationship Hubble’s.

The Expanding Universe Wednesday, October 22 Next planetarium show: Thurs, Nov. 6.

The Expanding Universe

Main-Sequence Fitting 1.Find a star and measure its apparent brightness (F). 2.Take its spectrum, identify its spectral type. 3.Use its spectral type to.

9. Distances in open space Serbian team Regional Center For Talented Youth Belgrade II.

The Big Bang etc getting Time off to a good start 1 Origins.

Earth Sun Star 2. Careful measurement of a celestial object’s position in the sky (astrometry) may be used to determine its distance Define the terms parallax,

1B11 Foundations of Astronomy Cosmic distance scale Liz Puchnarewicz

Announcements Exam 4 is Monday May 4. Tentatively will cover Chapters 9, 10, 11 & 12 (maybe) Sample questions will be posted soon Project Presentations.

The Big Bang Thursday, January 17.

How Far Away Are The Stars?. Distances in the Solar System Kepler’s Third Law relates period and distance Defines a relative distance scale One accurate.

Goal: To understand how we know distances to various objects (the distance scale) Objectives: 1)To learn about Radar (the sun) 2)To learn about Parallax.

Parallax through the ages. 1 PARSEC = distance in AU if the difference in degree measurements is 1 arcsecond (1/60 th of 1/60 th of a degree)

PHYS 205 Surveying the Stars PHYS 205 Parallax The apparent change in the direction of the remote object due to a change in the vantage point of the.

The Inverse Square Law and Surface Area

Cosmic Distances How do we determine the distance to celestial objects? No single method works at all distances… close, intermediate and far. Astronomers.

Name: Setiawan Office: S , Phys. Departm. Phone: Consultation: Wed Tutorial.

Cosmology and extragalactic astronomy Mat Page Mullard Space Science Lab, UCL 5. The cosmic distance ladder.

Lecture 16: Deep Space Astronomy 1143 – Spring 2014.

Announcements HW #1 will be returned on Wednesday Problem #7 – I wrote the distance incorrectly, should have been x1019 km. But don’t change your.

Distances: mostly Unit 54

AST101 The Nature of the Nebulae. Tuning Fork Diagram.

ASTROPHYSICS PROBLEMS. a) Describe what is meant by a nebula. EX: an intergalactic cloud of gas and dust where all stars begin to form.

Charles Hakes Fort Lewis College1. Charles Hakes Fort Lewis College2.

H205 Cosmic Origins  Today: Galaxies (Ch. 20)  Wednesday: Galaxy Evolution (Ch. 21)  EP 4 & Reflection 1 on Wednesday APOD.

 Distance is the most important & most difficult quantity to measure in Astronomy  Method of Trigonometric Parallaxes  Direct geometric method of finding.

Chapter 20 Cosmology. Hubble Ultra Deep Field Galaxies and Cosmology A galaxy’s age, its distance, and the age of the universe are all closely related.

Hubble Law, Distances & Structure in the Universe Today’s Lecture: Hubble Law, Distances & Structure in the Universe Hubble Law Cosmic Distances Galaxy.

Lecture 32: Galaxies We see that scattered through space out to infinite distances, there exist similar systems of stars, and that all of creation, in.

Chapter 20 Galaxies And the Foundation of Modern Cosmology

Astronomical distances.

Option D1 & D2: Measuring Stellar Distances

Measuring Distances in Space

Cosmic Distances How to measure distances Primary distance indicators

GALAXIES, GALAXIES, GALAXIES!

Stellar Distances SL/HL – Option E.3.

Learning Goals: I will:

9. Distances in open space

Devil physics The baddest class on campus IB Physics

Objectives: To learn about Radar (the sun)

The Cosmic Distance Ladder

The Inverse Square Law and Surface Area

Homework: Due at Midnight

Distance Ladder How can you calculate the distance to a star or galaxy without ever leaving the Earth?

Classification of stars

Chapter 20 Galaxies Determining Distance

Galaxies Island Universes.

Celestial Distances A Galaxy 150 Million Light Years From Earth

Astronomical Distances

Stellar position, distance, and properties

Cosmic Dist. Ladder: Why Is it a Ladder?

After Bellwork, Read the FYI on the “Cosmological Distance Ladder” then answer the two questions in your science journal.

Presentation transcript:

Announcements Third exam is Friday, October 29 Review on Wednesday, October 27 Please hand in or e-mail questions for the review

Cosmic Distances How to measure distances Primary distance indicators Secondary and tertiary distance indicators Recession of galaxies Expansion of the Universe

Stellar Parallax As the Earth moves from one side of the Sun to the other, a nearby star will seem to change its position relative to the distant background stars. d = 1 / p d = distance to nearby star in parsecs p = parallax angle of that star in arcseconds

Stellar Parallax Most accurate parallax measurements are from the European Space Agency’s Hipparcos mission. Hipparcos could measure parallax as small as 0.001 arcseconds or distances as large as 1000 pc. How to find distance to objects farther than 1000 pc?

Flux and Luminosity Flux decreases as we get farther from the star – like 1/distance2 Mathematically, if we have two stars A and B

Standard Candles

Standard Candles Measure the distance to star A to be 200 pc. Measure the flux of star A. Measure the flux of star B with same spectral type and luminosity class to be lower by a factor of 1600 Find the distance to star B

Distances to galaxies Standard candles, such as Cepheid variables, the most luminous supergiants, globular clusters, H II regions, and supernovae in a galaxy, are used in estimating intergalactic distances.

The Distance Ladder Each stage in the ladder overlaps the previous and next Cepheid distances are critical Tully-Fisher, fundamental plane apply to whole galaxies Supernova are now the best estimators at large distances

Distances and velocities of galaxies If you measure the distances to a large set of galaxies and also measure the speed of the galaxies using the redshift, what do you find?

Hubble expansion v = H0d

Expansion of the Universe

Expansion of the Universe Blow up the balloon to about a 3 inch diameter. Twist the neck and hold it closed so that no air escapes, but do NOT make a knot because you will need to blow it up some more. Make SIX dots on its surface to represent galaxies and label them A-F. Measure and record the distances from cluster A to each of the other 5 clusters. Measure and record the distances from cluster D to each of the other 5 clusters. Blow up the balloon up more, to a diameter of about 6 inches. Measure the distances between the same clusters again and record them.

Expansion of the Universe Are all the other clusters moving away from cluster A? Are all the other clusters moving away from cluster D? Is there a cluster that could be considered to be at the center of the universe as represented by the surface of the balloon?