Class #14/15 14/16 October 2008

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "Class #14/15 14/16 October 2008"

Transcription

1 Class #14/15 14/16 October 2008

2 Thursday, Oct 23 in class You ll be given equations and constants Bring a calculator, paper Closed book/notes Topics Stellar evolution/hr-diagram/manipulate the IMF ISM phases/detection techniques Distribution of stars in MWG and other spirals How do we measure the MWG s rotation curve? Relationships between velocity, mass, potential Tracers of star formation Basic differences between spirals and ellipticals (including spectra) Reading Chapters: 1,2,3,5 Lectures

3 Basic Properties of Elliptical Galaxies Stellar Populations in Ellipticals Stellar Kinematics

4 Morelli et al 2008

5

6

7 Formation did all ellipticals form via mergers of gas-rich disk galaxies? Are central cusps evidence of central black holes? What is the role of cannibalism and the formation of extended stellar halos? What is the origin of gaseous shells around some ellipticals? What is the true shape of elliptical galaxies?

8

9 Abell Cluster Coma Cluster

10 Surface photometry I(r)=I e exp{-7.67[(r/r e ) 1/4-1]} r 1/4 law R e = effective radius at which ½ of light is emitted Comparable to bulges of disk galaxies Classification: E0-E7 describing increase in flattening Stellar populations: old, metal rich Environment: dense, usually in clusters (morphology-density relationship)

11 Deviations from basic structure Centers in cd galaxies the surface brightness turns up in the center. Halos some have extended halos (excess light at large radii) What distinguishes ellipticals from spirals? Ratio of V ROT /σ V ROT is the circular velocity σ is the velocity dispersion In MWG V ROT ~220 km s -1, σ~50 km s -1 ; it s the opposite in ellipticals Ellipticals are kinematically dominated by the velocity dispersion rather than the circular velocity Presence of large amounts of cool gas

12 Basic colors redder than spirals Radial color gradient Metallicity gradient: d[fe/h]/dlog 10 r = Based on Mg, Fe lines spectrum (compare with a spiral) Look like G or F stars; prominent Mg lines Need high resolution spectra over the 400.0nm nm range + stellar absorption line models Age-abundance degeneracy Can use Hβ line strengths as age indicator

13 Trager et al Age spread: 2-12 Gyr Nearly solar metallicity ([Z/H]) Slightly subsolar [Fe/H] Yields a high [Mg/Fe] ratio Other fits: old population with frosting of younger stars Bottom line: good fraction of old stars, but how old and real fraction is not well known.

14 Trager et al. 2000

15 Cool gas Usually outside of main galaxy Associated with shells Disks out to large radii (exception: dwarf ellipticals with nuclear clouds) No correlation between presence of cool gas and any other property of the galaxy Ionized gas not much Hot gas lots

16 L X goes as L B (empirical result) ρ gas goes as r -3/2 M gas ~ M o Origin of hot gas Reservoir External Internal Mass return from AGB stars ~1.5 x M o yr -1 L o -1 Heated by SNe, thermal motion of stars at km s -1

17

18

19 Measuring intrinsic shape/potential 1. Surface photometry mass distribution potential (Φ, M(r) model) orbit library superposition of orbits iterate 2. Surface photometry + resolved velocity fields and velocity dispersion maps You measure of line-of-sight velocity distribution v los = F(v los )v los dv los Then, σ 2 = (v los -v los ) 2 F(v los ) dv los This accounts for the streaming and random motion of stars.

20 LOSVD Assume a gaussian (don t we always?) and this makes things easier. F exp[-(v los -v los ) 2 /2σ los2 ] exp -b (b = (1/2)w 2 ) This all yields a symmetric line profile. Remember we re sampling a specific absorption feature (e.g. a Mg II line) But life isn t all that symmetric, so we need some way to describe deviations from gaussian Gauss-Hermite series which combine a gaussian with a polynomial F goes as e -k [1 + k=3n h k H k (w)] (this is a polynomial of order k, with some coefficient h)

21 1. Describe stellar kinematics with four terms: v, σ 2, h 3, h Third term: h 3 (2w 3-3w)/(3 1/2 ) 2. Fourth term: h 4 (4w 4-12w 2 +1)/(24 1/2 ) 2. h 3 measures skewness or deviation from symmetry. Large positive h 3 represents a secondary bump at v > v so that the peak of the line is now < v 3. h 4 measures kurtosis or symmetric departures from a gaussian. Large h 4 yields a boxy profile centered on v

22

23

24

25 Main lines are Hβ, Mg II, Fe I (generally in blue part of the spectrum Case study: NGC 1399 (cd in Fornax) V ~ km s -1 σ 2 ~ km s -1 h 3 ~0.02, h 4 ~0.02 Next step: pick a potential that will fit observed kinematics and surface brightness profile

26 e.g.: Φ(R,Z)=(1/2)v 02 ln(r c2 +R 2 ) Maximize the things you know (stars) Use four key kinematic parameters Fit weirdness (e.g. steep rise in velocity dispersion in the center by including a black hole see SOS program) Alternatively, use tracers at large radii (PN and GCs) to obtain overall velocity

27 M/L ratio increases with R M/r = 5 x M 0 kpc -1 M/L ~ in some cases Kinematics dominated by a dark halo beyond 1-2 R e flat σ vs R curves (just like spirals) (further confirmation of dark halo comes from power law like distribution of hot x-ray emitting gas)

28

29

Ellipticals. Elliptical galaxies: Elliptical galaxies: Some ellipticals are not so simple M89 E0

Ellipticals. Elliptical galaxies: Elliptical galaxies: Some ellipticals are not so simple M89 E0 Elliptical galaxies: Ellipticals Old view (ellipticals are boring, simple systems)! Ellipticals contain no gas & dust! Ellipticals are composed of old stars! Ellipticals formed in a monolithic collapse,

More information

Faber-Jackson relation: Fundamental Plane: Faber-Jackson Relation

Faber-Jackson relation: Fundamental Plane: Faber-Jackson Relation Faber-Jackson relation: Faber-Jackson Relation In 1976, Faber & Jackson found that: Roughly, L! " 4 More luminous galaxies have deeper potentials Can show that this follows from the Virial Theorem Why

More information

Elliptical Galaxies. Old view: ellipticals are boring, simple systems

Elliptical Galaxies. Old view: ellipticals are boring, simple systems Eliptical Galaxies Elliptical Galaxies Old view: ellipticals are boring, simple systems Ellipticals contain no gas & dust Ellipticals are composed of old stars Ellipticals formed in a monolithic collapse,

More information

Lecture 6: distribution of stars in. elliptical galaxies

Lecture 6: distribution of stars in. elliptical galaxies Lecture 6: distribution of stars in topics: elliptical galaxies examples of elliptical galaxies different classes of ellipticals equation for distribution of light actual distributions and more complex

More information

Observational properties of ellipticals

Observational properties of ellipticals Observational properties of ellipticals Ellipticals are deceptively simple it is so tempting to treat them as a pressure supported gas of stars but this is not correct. Too bad that only dwarf ellipticals

More information

Galaxy Formation. Leading questions for today How do visible galaxies form inside halos? Why do galaxies/halos merge so easily?

Galaxy Formation. Leading questions for today How do visible galaxies form inside halos? Why do galaxies/halos merge so easily? 8-5-2015see http://www.strw.leidenuniv.nl/ franx/college/ mf-sts-2015-c9-1 8-5-2015see http://www.strw.leidenuniv.nl/ franx/college/ mf-sts-2015-c9-2 Galaxy Formation Leading questions for today How do

More information

Ay 20 - Fall Lecture 16. Our Galaxy, The Milky Way

Ay 20 - Fall Lecture 16. Our Galaxy, The Milky Way Ay 20 - Fall 2004 - Lecture 16 Our Galaxy, The Milky Way Our Galaxy - The Milky Way Overall structure and major components The concept of stellar populations Stellar kinematics Galactic rotation and the

More information

Elliptical Galaxies. Houjun Mo. April 19, 2004. Basic properties of elliptical galaxies. Formation of elliptical galaxies

Elliptical Galaxies. Houjun Mo. April 19, 2004. Basic properties of elliptical galaxies. Formation of elliptical galaxies Elliptical Galaxies Houjun Mo April 19, 2004 Basic properties of elliptical galaxies Formation of elliptical galaxies Photometric Properties Isophotes of elliptical galaxies are usually fitted by ellipses:

More information

The Milky Way Galaxy. Our Home Away From Home

The Milky Way Galaxy. Our Home Away From Home The Milky Way Galaxy Our Home Away From Home Lecture 23-1 Galaxies Group of stars are called galaxies Our star, the Sun, belongs to a system called The Milky Way Galaxy The Milky Way can be seen as a band

More information

The Milky Way Galaxy. This is NOT the Milky Way galaxy! It s a similar one: NGC 4414.

The Milky Way Galaxy. This is NOT the Milky Way galaxy! It s a similar one: NGC 4414. The Milky Way Galaxy This is NOT the Milky Way galaxy! It s a similar one: NGC 4414. 1 The Milky Way Galaxy 2 Interactive version 3 Take a Giant Step Outside the Milky Way Artist's Conception Example (not

More information

arxiv:astro-ph/0101553v1 31 Jan 2001

arxiv:astro-ph/0101553v1 31 Jan 2001 Evidence for Large Stellar Disks in Elliptical Galaxies. Andreas Burkert and Thorsten Naab Max-Planck-Institut für Astronomie, D-69242 Heidelberg, Germany arxiv:astro-ph/0101553v1 31 Jan 2001 Abstract.

More information

Measuring the Rotational Speed of Spiral Galaxies and Discovering Dark Matter

Measuring the Rotational Speed of Spiral Galaxies and Discovering Dark Matter Measuring the Rotational Speed of Spiral Galaxies and Discovering Dark Matter Activity UCIObs 9 Grade Level: College Source: Copyright (2009) by Rachel Kuzio de Naray & Tammy Smecker-Hane. Contact tsmecker@uci.edu

More information

PART 3 Galaxies. Stars in the Milky Way

PART 3 Galaxies. Stars in the Milky Way PART 3 Galaxies Stars in the Milky Way A galaxy is a large collection of billions of stars The galaxy in which the Sun is located is called the Milky Way From our vantage point inside the galaxy, the Milky

More information

PS 224, Fall 2014 HW 4

PS 224, Fall 2014 HW 4 1. True or False? Explain in one or two short sentences. (2x10 points) a. The fact that we have not yet discovered an Earth-size extrasolar planet in an Earth-like orbit tells us that such planets must

More information

Our Galaxy, the Milky Way

Our Galaxy, the Milky Way Our Galaxy, the Milky Way In the night sky, the Milky Way appears as a faint band of light. Dusty gas clouds obscure our view because they absorb visible light. This is the interstellar medium that makes

More information

arxiv:astro-ph/0407219v1 12 Jul 2004

arxiv:astro-ph/0407219v1 12 Jul 2004 Astronomy & Astrophysics manuscript no. 1414 December 16, 2013 (DOI: will be inserted by hand later) Line-of-sight velocity distribution corrections for Lick/IDS indices of early-type galaxies Harald Kuntschner

More information

The Milky Way Galaxy. Studying Its Structure Mass and Motion of the Galaxy Metal Abundance and Stellar Populations Spiral Structure and Star Formation

The Milky Way Galaxy. Studying Its Structure Mass and Motion of the Galaxy Metal Abundance and Stellar Populations Spiral Structure and Star Formation The Milky Way Galaxy Studying Its Structure Mass and Motion of the Galaxy Metal Abundance and Stellar Populations Spiral Structure and Star Formation The Milky Way Almost everything we see in the night

More information

Observing the Universe

Observing the Universe Observing the Universe Stars & Galaxies Telescopes Any questions for next Monday? Light Doppler effect Doppler shift Doppler shift Spectra Doppler effect Spectra Stars Star and planet formation Sun Low-mass

More information

Modeling Galaxy Formation

Modeling Galaxy Formation Galaxy Evolution is the study of how galaxies form and how they change over time. As was the case with we can not observe an individual galaxy evolve but we can observe different galaxies at various stages

More information

Lecture Outlines. Chapter 23. Astronomy Today 7th Edition Chaisson/McMillan Pearson Education, Inc.

Lecture Outlines. Chapter 23. Astronomy Today 7th Edition Chaisson/McMillan Pearson Education, Inc. Lecture Outlines Chapter 23 Astronomy Today 7th Edition Chaisson/McMillan Chapter 23 The Milky Way Galaxy Units of Chapter 23 23.1 Our Parent Galaxy 23.2 Measuring the Milky Way Early Computers 23.3 Galactic

More information

Elliptical Galaxies. Virgo Cluster: distance 15Mpc

Elliptical Galaxies. Virgo Cluster: distance 15Mpc Elliptical Galaxies Virgo Cluster: distance 15Mpc Elliptical Galaxies Elliptical galaxies are thought to be the simplest of all types of galaxies. Yet, detailed analysis shows that they are much more complicated

More information

The Milky Way. The Milky Way. First Studies of the Galaxy. Determining the Structure of the Milky Way. Galactic Plane.

The Milky Way. The Milky Way. First Studies of the Galaxy. Determining the Structure of the Milky Way. Galactic Plane. The Milky Way The Milky Way Almost everything we see in the night sky belongs to the Milky Way. 1 We see most of the Milky Way as a faint band of light across the sky. From outside, our Milky Way might

More information

Chapter 15.3 Galaxy Evolution

Chapter 15.3 Galaxy Evolution Chapter 15.3 Galaxy Evolution Elliptical Galaxies Spiral Galaxies Irregular Galaxies Are there any connections between the three types of galaxies? How do galaxies form? How do galaxies evolve? P.S. You

More information

Rough subdivision. Characteristic values for E s (Schneider 2006). Elliptical galaxies. Elliptical galaxies

Rough subdivision. Characteristic values for E s (Schneider 2006). Elliptical galaxies. Elliptical galaxies Rough subdivision Normal ellipticals. Giant ellipticals (ge s), intermediate luminosity (E s), and compact ellipticals (ce s), covering a range of luminosities from M B 23 m to M B 15 m. Dwarf ellipticals

More information

Dark Matter in Elliptical Galaxies?

Dark Matter in Elliptical Galaxies? Chapter 12 Dark Matter in Elliptical Galaxies? By analogy with disk galaxies, one might expect that the velocity dispersion profile of an elliptical galaxy can be analyzed to inferr the total mass and

More information

The Hidden Lives of Galaxies. Jim Lochner, USRA & NASA/GSFC

The Hidden Lives of Galaxies. Jim Lochner, USRA & NASA/GSFC The Hidden Lives of Galaxies Jim Lochner, USRA & NASA/GSFC What is a Galaxy? Solar System Distance from Earth to Sun = 93,000,000 miles = 8 light-minutes Size of Solar System = 5.5 light-hours What is

More information

The CGM around Dwarf Galaxies

The CGM around Dwarf Galaxies The CGM around Dwarf Galaxies Rongmon Bordoloi STScI + the COS-Halos Team What is the CGM? Shen et al. 212 jectedcolumndensityinacubeof5(proper)kpc Diffuse gas, including metals and dust, o2en on extending

More information

The Inner Milky Way has a low dark matter fraction and a near Kroupa IMF

The Inner Milky Way has a low dark matter fraction and a near Kroupa IMF The Inner Milky Way has a low dark matter fraction and a near Kroupa IMF Constraints from microlensing and dynamical modelling Microlensing event not to scale Chris Wegg, Ortwin Gerhard & Matthieu Portail

More information

Qué pasa si n = 1 y n = 4?

Qué pasa si n = 1 y n = 4? Galaxias Elípticas Qué pasa si n = 1 y n = 4? Isophotal Shapes For normal elliptical galaxies the axis ratio lies in the range 0.3

More information

4/27/ Unseen Influences in the Cosmos. Chapter 18: Dark Matter, Dark Energy, and the Fate of the Universe.

4/27/ Unseen Influences in the Cosmos. Chapter 18: Dark Matter, Dark Energy, and the Fate of the Universe. Lecture Outline 18.1 Unseen Influences in the Cosmos Chapter 18: Dark Matter, Dark Energy, and the Fate of the Universe Our goals for learning: What do we mean by dark matter and dark energy? What do we

More information

Chemical tagging with. Ricardo Schiavon

Chemical tagging with. Ricardo Schiavon Chemical tagging with Ricardo Schiavon Stellar Populations Newton Meeting São Paulo, November 30, 2015 Chemical tagging with Discovery of a new stellar population in the Galactic bulge Astrophysics Research

More information

Elliptical Galaxies. Galaxies and Their Properties, Part II: Fine Structure in E-Galaxies: A Signature of Recent Merging

Elliptical Galaxies. Galaxies and Their Properties, Part II: Fine Structure in E-Galaxies: A Signature of Recent Merging Elliptical Galaxies Ay 21 - Lecture 12 Galaxies and Their Properties, Part II: Old view: ellipticals are boring, simple systems Ellipticals contain no gas & dust Ellipticals are composed of old stars Ellipticals

More information

Be Stars. By Carla Morton

Be Stars. By Carla Morton Be Stars By Carla Morton Index 1. Stars 2. Spectral types 3. B Stars 4. Be stars 5. Bibliography How stars are formed Stars are composed of gas Hydrogen is the main component of stars. Stars are formed

More information

Measuring the mass of galaxies Luminous matter in a galaxy: stars (of different masses) gas (mostly hydrogen) Can detect these directly using optical

Measuring the mass of galaxies Luminous matter in a galaxy: stars (of different masses) gas (mostly hydrogen) Can detect these directly using optical Measuring the mass of galaxies Luminous matter in a galaxy: stars (of different masses) gas (mostly hydrogen) Can detect these directly using optical and radio telescopes - get an estimate of how much

More information

in the Milky Way s dsphs

in the Milky Way s dsphs Probes of Dark Matter on Galaxy Scales Monterey, CA July 15, 2013 The Diversity of Dark Matter Profiles in the Milky Way s dsphs John Jardel, University of Texas Dark Matter & Galaxy Formation Lots of

More information

Learning Objectives. at the center of our Galaxy...why were they wrong? are globular clusters? Cepheid Variable stars?

Learning Objectives. at the center of our Galaxy...why were they wrong? are globular clusters? Cepheid Variable stars? Our Milky Way Learning Objectives! What is the Milky Way? The Herschels thought we were at the center of our Galaxy...why were they wrong?! How did Shapley prove we aren t at the center? What are globular

More information

In studying the Milky Way, we have a classic problem of not being able to see the forest for the trees.

In studying the Milky Way, we have a classic problem of not being able to see the forest for the trees. In studying the Milky Way, we have a classic problem of not being able to see the forest for the trees. A panoramic painting of the Milky Way as seen from Earth, done by Knut Lundmark in the 1940 s. The

More information

Direct Detections of Young Stars in Nearby Ellipticals

Direct Detections of Young Stars in Nearby Ellipticals Direct Detections of Young Stars in Nearby Ellipticals (NRAO Green Bank) Joel N. Bregman (University of Michigan) Click icon to add picture ApJ, in press (arxiv:1205.1066) Red and Dead Conventional wisdom:

More information

Data Provided: A formula sheet and table of physical constants is attached to this paper. DARK MATTER AND THE UNIVERSE

Data Provided: A formula sheet and table of physical constants is attached to this paper. DARK MATTER AND THE UNIVERSE Data Provided: A formula sheet and table of physical constants is attached to this paper. DEPARTMENT OF PHYSICS AND ASTRONOMY Autumn Semester (2014-2015) DARK MATTER AND THE UNIVERSE 2 HOURS Answer question

More information

A Universe of Galaxies

A Universe of Galaxies A Universe of Galaxies Today s Lecture: Other Galaxies (Chapter 16, pages 366-397) Types of Galaxies Habitats of Galaxies Dark Matter Other Galaxies Originally called spiral nebulae because of their shape.

More information

DIRECT ORBITAL DYNAMICS: USING INDEPENDENT ORBITAL TERMS TO TREAT BODIES AS ORBITING EACH OTHER DIRECTLY WHILE IN MOTION

DIRECT ORBITAL DYNAMICS: USING INDEPENDENT ORBITAL TERMS TO TREAT BODIES AS ORBITING EACH OTHER DIRECTLY WHILE IN MOTION 1 DIRECT ORBITAL DYNAMICS: USING INDEPENDENT ORBITAL TERMS TO TREAT BODIES AS ORBITING EACH OTHER DIRECTLY WHILE IN MOTION Daniel S. Orton email: dsorton1@gmail.com Abstract: There are many longstanding

More information

Highlights from the VLA/ANGST Survey

Highlights from the VLA/ANGST Survey Highlights from the VLA/ANGST Survey Evan Skillman U. Minnesota Gas in Galaxies 2011: From Cosmic Web to Molecular Clouds Kloster Seeon, Germany 16/06/2011 VLA/ANGST The ANGST HST Treasury Project allowed

More information

Low-Mass X-Ray Binary Models for Ellipticals NGC3379 and NGC4278

Low-Mass X-Ray Binary Models for Ellipticals NGC3379 and NGC4278 Low-Mass X-Ray Binary Models for Ellipticals NGC3379 and NGC4278 Tassos Fragos with V. Kalogera, K. Belczynski, G. Fabbiano et al. Department of Physics and Astronomy Northwestern University MODEST 7b

More information

Intermediate-Mass Black Holes (IMBHs) in Globular Clusters? HST Proper Motion Constraints. Roeland van der Marel

Intermediate-Mass Black Holes (IMBHs) in Globular Clusters? HST Proper Motion Constraints. Roeland van der Marel Intermediate-Mass Black Holes (IMBHs) in Globular Clusters? HST Proper Motion Constraints Roeland van der Marel Why Study IMBHs in Globular Clusters (GCs)? IMBHs: IMBHs can probe a new BH mass range, between

More information

Understanding the Rotation of the Milky Way Using Radio Telescope Observations1

Understanding the Rotation of the Milky Way Using Radio Telescope Observations1 Understanding the Rotation of the Milky Way Using Radio Telescope Observations1 Alexander L. Rudolph Professor of Physics and Astronomy, Cal Poly Pomona Professeur Invité, Université Pierre et Marie Curie

More information

Name Class Date. true

Name Class Date. true Exercises 131 The Falling Apple (page 233) 1 Describe the legend of Newton s discovery that gravity extends throughout the universe According to legend, Newton saw an apple fall from a tree and realized

More information

Astro 130, Fall 2011, Homework, Chapter 17, Due Sep 29, 2011 Name: Date:

Astro 130, Fall 2011, Homework, Chapter 17, Due Sep 29, 2011 Name: Date: Astro 130, Fall 2011, Homework, Chapter 17, Due Sep 29, 2011 Name: Date: 1. If stellar parallax can be measured to a precision of about 0.01 arcsec using telescopes on Earth to observe stars, to what distance

More information

The Milky Way Galaxy is Heading for a Major Cosmic Collision

The Milky Way Galaxy is Heading for a Major Cosmic Collision The Milky Way Galaxy is Heading for a Major Cosmic Collision Roeland van der Marel (STScI) [based on work with a team of collaborators reported in the Astrophysical Journal July 2012] Hubble Science Briefing

More information

Chapter 5 Light and Matter: Reading Messages from the Cosmos

Chapter 5 Light and Matter: Reading Messages from the Cosmos Chapter 5 Light and Matter: Reading Messages from the Cosmos Messages Interactions of Light and Matter The interactions determine everything we see, including what we observe in the Universe. What is light?

More information

S0 galaxy NGC 2787. Marcella Carollo, HST.

S0 galaxy NGC 2787. Marcella Carollo, HST. S0 galaxy NGC 2787. Marcella Carollo, HST. Dust lane in NGC 5128. Marina Rejkuba, ESO. Peculiar E galaxy NGC 1316. Paul Goudfrooij, HST. Dust-lane E galaxy NGC 5266. Carnegie Atlas of Galaxies. 1994ApJ...43

More information

Milky Way Galaxy Determining the size/extent counting stars (doesn t work) Variable Stars Red Giants/Supergiants Instability Strip Hydrostatic

Milky Way Galaxy Determining the size/extent counting stars (doesn t work) Variable Stars Red Giants/Supergiants Instability Strip Hydrostatic Milky Way Galaxy Determining the size/extent counting stars (doesn t work) Variable Stars Red Giants/Supergiants Instability Strip Hydrostatic Equilibrium Cepheids characteristics Type I, II differences

More information

165 points. Name Date Period. Column B a. Cepheid variables b. luminosity c. RR Lyrae variables d. Sagittarius e. variable stars

165 points. Name Date Period. Column B a. Cepheid variables b. luminosity c. RR Lyrae variables d. Sagittarius e. variable stars Name Date Period 30 GALAXIES AND THE UNIVERSE SECTION 30.1 The Milky Way Galaxy In your textbook, read about discovering the Milky Way. (20 points) For each item in Column A, write the letter of the matching

More information

Element abundance ratios in stellar population modelling

Element abundance ratios in stellar population modelling Element abundance ratios in stellar population modelling Daniel Thomas University of Portsmouth Absorption features in galaxies Key for the derivation of chemical element abundance ratios Stars not resolved

More information

Populations and Components of the Milky Way

Populations and Components of the Milky Way Chapter 2 Populations and Components of the Milky Way Our perspective from within the Milky Way gives us an opportunity to study a disk galaxy in detail. At the same time, it s not always easy to relate

More information

The Discovery of Galaxies Kant proposed Island Universes Earl of Rosse built 72 telescope in 1845

The Discovery of Galaxies Kant proposed Island Universes Earl of Rosse built 72 telescope in 1845 The Discovery of Galaxies 1755 Kant proposed Island Universes Earl of Rosse built 72 telescope in 1845 M51Whirlpool Galaxy Thru binoculars Earl of Rosse sketched the spiral nebulae Modern image Andromeda

More information

Fundamental (Sub)stellar Parameters: Metallicity. PHY 688, Lecture 12

Fundamental (Sub)stellar Parameters: Metallicity. PHY 688, Lecture 12 Fundamental (Sub)stellar Parameters: Metallicity PHY 688, Lecture 12 Outline Review of previous lecture pressure broadening as an indicator of surface gravity lower-gravity objects are younger, less massive

More information

A. Answer all of the following multiple choice questions (50%):

A. Answer all of the following multiple choice questions (50%): Core 30.01 - Cosmology Fall 2006 Prof. Micha Tomkiewicz Final Exam: My Name A. Answer all of the following multiple choice questions (50%): 1. The universe became matter dominated approximately after the

More information

The formation of the galaxy is believed to be similar to the formation of the solar system.

The formation of the galaxy is believed to be similar to the formation of the solar system. The formation of the galaxy is believed to be similar to the formation of the solar system. All the gas & dust collapsed into a disk. During the time that stars were being formed, our galaxy didn t have

More information

The Evolution of GMCs in Global Galaxy Simulations

The Evolution of GMCs in Global Galaxy Simulations The Evolution of GMCs in Global Galaxy Simulations image from Britton Smith Elizabeth Tasker (CITA NF @ McMaster) Jonathan Tan (U. Florida) Simulation properties We use the AMR code, Enzo, to model a 3D

More information

12. The Milky Way Galaxy

12. The Milky Way Galaxy Astronomy 110: SURVEY OF ASTRONOMY 12. The Milky Way Galaxy 1. Structure of the Milky Way 2. Generations of Stars 3. Origin and Center The Milky Way Galaxy is a vast pinwheel of stars and gas turning within

More information

AST Cosmology and extragalactic astronomy. Lecture 12. Structure of Dark Matter Halos & The Missing Satellites Problem.

AST Cosmology and extragalactic astronomy. Lecture 12. Structure of Dark Matter Halos & The Missing Satellites Problem. AST4320 - Cosmology and extragalactic astronomy Lecture 12 Structure of Dark Matter Halos & The Missing Satellites Problem. 1 AST4320 - Cosmology and extragalactic astronomy Lecture 12 Outline Comparison

More information

ROE, Edinburgh, 20 April 2006. Observational Constraints on the Acceleration Discrepancy Problem. Stacy McGaugh University of Maryland

ROE, Edinburgh, 20 April 2006. Observational Constraints on the Acceleration Discrepancy Problem. Stacy McGaugh University of Maryland ROE, Edinburgh, 20 April 2006 Observational Constraints on the Acceleration Discrepancy Problem Stacy McGaugh University of Maryland What gets us into trouble is not what we don t know. It s what we know

More information

The Milky Way Galaxy (ch. 23)

The Milky Way Galaxy (ch. 23) Notes on Ch. 23 and 24. The Milky Way Galaxy (ch. 23) [Exceptions: We won t discuss sec. 23.7 (Galactic Center) in class, but look it over in order to just get the most basic point I might put a question

More information

Galaxy Classification and Evolution

Galaxy Classification and Evolution name Galaxy Classification and Evolution Galaxy Morphologies In order to study galaxies and their evolution in the universe, it is necessary to categorize them by some method. A classification scheme generally

More information

19. Our Galaxy The Milky Way Revealed. Our goals for learning: Regions of the Milky Way Galaxy. Regions of the Milky Way Galaxy

19. Our Galaxy The Milky Way Revealed. Our goals for learning: Regions of the Milky Way Galaxy. Regions of the Milky Way Galaxy 19. Our Galaxy The infinitude of creation is great enough to make a world, or a Milky Way of worlds, look in comparison with it what a flower or an insect does in comparison with the Earth. 19.1 The Milky

More information

Stellar populations and kinematics of dwarf galaxies in the Virgo cluster with Gemini-GMOS

Stellar populations and kinematics of dwarf galaxies in the Virgo cluster with Gemini-GMOS Stellar populations and kinematics of dwarf galaxies in the Virgo cluster with Gemini-GMOS Richard McDermid Macquarie University / Australian Astronomical Observatory MACQUARIE University Dwarfs Test Models:

More information

Milky Way Galaxy. A. Star counts. B. Core and Arms. C. Galaxy Rotation. Milky Way. A1a. Milky Way 4 A1b. Milky Way: Galactic Equator 5

Milky Way Galaxy. A. Star counts. B. Core and Arms. C. Galaxy Rotation. Milky Way. A1a. Milky Way 4 A1b. Milky Way: Galactic Equator 5 Milky Way Galaxy Milky Way A. Star counts B. Core and Arms C. Galaxy Rotation Dr. Bill Pezzaglia Updated: Nov, Aa. Milky Way 4 Ab. Milky Way: Galactic Equator a. Galileo Galilei (64-64) 6 Ac. 7 Thomas

More information

1 A Solar System Is Born

1 A Solar System Is Born CHAPTER 3 1 A Solar System Is Born SECTION Formation of the Solar System BEFORE YOU READ After you read this section, you should be able to answer these questions: What is a nebula? How did our solar system

More information

UNIT V. Earth and Space. Earth and the Solar System

UNIT V. Earth and Space. Earth and the Solar System UNIT V Earth and Space Chapter 9 Earth and the Solar System EARTH AND OTHER PLANETS A solar system contains planets, moons, and other objects that orbit around a star or the star system. The solar system

More information

Proceedings of the NATIONAL ACADEMY OF SCIENCES

Proceedings of the NATIONAL ACADEMY OF SCIENCES Proceedings of the NATIONAL ACADEMY OF SCIENCES Volume 55 * Number 1 * January 15, 1966 DYNAMICS OF SPHERICAL GALAXIES, II* BY PHILIP M. CAMPBELL LAWRENCE RADIATION LABORATORY, LIVERMORE, CALIFORNIA Communicated

More information

TMT/IRMS: the Science Case. Bahram Mobasher University of California, Riverside

TMT/IRMS: the Science Case. Bahram Mobasher University of California, Riverside TMT/IRMS: the Science Case Bahram Mobasher University of California, Riverside IRMS = MOSFIRE + TMT/NFIRAOS IRMS provides a relatively cheap near-ir multi-slit spectrograph and imager on TMT. With no significant

More information

Origins of the Cosmos Summer 2016. Pre-course assessment

Origins of the Cosmos Summer 2016. Pre-course assessment Origins of the Cosmos Summer 2016 Pre-course assessment In order to grant two graduate credits for the workshop, we do require you to spend some hours before arriving at Penn State. We encourage all of

More information

Study Guide: Solar System

Study Guide: Solar System Study Guide: Solar System 1. How many planets are there in the solar system? 2. What is the correct order of all the planets in the solar system? 3. Where can a comet be located in the solar system? 4.

More information

Star Clusters and Stellar Dynamics

Star Clusters and Stellar Dynamics Ay 20 Fall 2004 Star Clusters and Stellar Dynamics (This file has a bunch of pictures deleted, in order to save space) Stellar Dynamics Gravity is generally the only important force in astrophysical systems

More information

X-ray Astronomy Field Guide

X-ray Astronomy Field Guide X-ray Astronomy Field Guide The Milky Way The word galaxy comes from a Greek word meaning "milky circle" or, more familiarly, "milky way." The white band of light across the night sky that we call the

More information

L=4 R 2 SBT 4. Galaxies (AS 7007) The physics of stars. A closer look at the physics of stars

L=4 R 2 SBT 4. Galaxies (AS 7007) The physics of stars. A closer look at the physics of stars Galaxies (AS 7007) Autumn 2007 Teacher: Göran Östlin Assistant: Jens Melinder Lecture 3, contents: - Stellar physics basics - Impact of stellar evolution on galaxies - Properties of local galaxies A closer

More information

Arrange the following forms of radiation from shortest wavelength to longest. optical gamma ray infrared x-ray ultraviolet radio

Arrange the following forms of radiation from shortest wavelength to longest. optical gamma ray infrared x-ray ultraviolet radio Arrange the following forms of radiation from shortest wavelength to longest. optical gamma ray infrared x-ray ultraviolet radio Which of the wavelength regions can completely penetrate the Earth s atmosphere?

More information

How the properties of galaxies are affected by the environment?

How the properties of galaxies are affected by the environment? How the properties of galaxies are affected by the environment? Reinaldo R. de Carvalho - DAS/INPE Marina Trevisan Reinaldo Rosa The activities in this project follow from the Tatiana Moura general context

More information

How is E-M Radiation Produced?

How is E-M Radiation Produced? How is E-M Radiation Produced? 1. Accelerate charged particle back and forth like they do at the radio station. 2. All solids or liquids with temperature above Absolute Zero emit E-M radiation. Absolute

More information

C. Morisset, N. Flores-Fajardo, G. Stasinska, L. Binette IA-UNAM, Paris-Meudon MNRAS in press, arxiv:

C. Morisset, N. Flores-Fajardo, G. Stasinska, L. Binette IA-UNAM, Paris-Meudon MNRAS in press, arxiv: C. Morisset, N. Flores-Fajardo, G. Stasinska, L. Binette IA-UNAM, Paris-Meudon MNRAS in press, arxiv:1104.0525 Summary What is the DIG? DIG is not an HII region, hotter? Heating the DIG, how? Grid of models

More information

Structure formation in modified gravity models

Structure formation in modified gravity models Structure formation in modified gravity models Kazuya Koyama Institute of Cosmology and Gravitation University of Portsmouth Dark energy v modified gravity Is cosmology probing the breakdown of general

More information

Lecture 12: Age, Metalicity, and Observations

Lecture 12: Age, Metalicity, and Observations Lecture 12: Age, Metalicity, and Observations Main sequence lifetime: M ' MS = 7 10 9 M ( ) L L.. *1 ' ( ) yr L L max R diagram giants Abundance Measurements Star spectra: absorption lines Gas spectra:

More information

i>clicker Questions A scientific law is something that has been proven to be true. A. True B. False C. Only in experimental sciences.

i>clicker Questions A scientific law is something that has been proven to be true. A. True B. False C. Only in experimental sciences. A scientific law is something that has been proven to be true. A. True B. False C. Only in experimental sciences. i>clicker Questions The fifth planet from the sun, the sixth planet and the seventh planet

More information

Chemical Enrichment in the Globular Cluster ω Centauri. Christian Johnson

Chemical Enrichment in the Globular Cluster ω Centauri. Christian Johnson Chemical Enrichment in the Globular Cluster ω Centauri Christian Johnson Globular Clusters as (not so) Simple Stellar Populations: The New Paradigm Globular Clusters as Simple Stellar Populations Stars

More information

2. Milky Way Structure of the Milky Way: a brief history

2. Milky Way Structure of the Milky Way: a brief history 1 2. Milky Way We know a great deal, perhaps more than any other galaxy, about the Milky Way (MW) due to our proximity. However, our inside position also hampers our understanding of the Milky Way. Fore

More information

Milky Way & Hubble Law

Milky Way & Hubble Law Milky Way & Hubble Law Astronomy 1 Elementary Astronomy LA Mission College Spring F2015 Quotes & Cartoon of the Day Happy Thanksgiving! Announcements 3rd midterm 12/3 I will drop the lowest midterm grade

More information

Dark Matter in the Milky Way - how to find it using Gaia and other surveys. Paul McMillan

Dark Matter in the Milky Way - how to find it using Gaia and other surveys. Paul McMillan Dark Matter in the Milky Way - how to find it using Gaia and other surveys Paul McMillan Surveys For All, 1st February 2016 Why do we care? On the biggest scales, the ΛCDM model works Why do we care? On

More information

Gravity slows down the expansion

Gravity slows down the expansion Key Concepts: Lecture 33: The Big Bang! Age of the Universe and distances from H 0 Gravity slows down the expansion Closed, Flat and Open Universes Evidence for the Big Bang (Galactic Evolution; Microwave

More information

KINEMATIC AGES OF THE CENTRAL STARS OF PLANETARY NEBULAE

KINEMATIC AGES OF THE CENTRAL STARS OF PLANETARY NEBULAE Revista Mexicana de Astronomía y Astrofísica, 47, 401 407 (2011) KINEMATIC AGES OF THE CENTRAL STARS OF PLANETARY NEBULAE W. J. Maciel, T. S. Rodrigues, and R. D. D. Costa Instituto de Astronomia, Geofísica

More information

The Chemical Composition of a Molecular Cloud at the Outer Edge of the Galaxy

The Chemical Composition of a Molecular Cloud at the Outer Edge of the Galaxy Carnegie Observatories Astrophysics Series, Vol. 4: Origin and Evolution of the Elements, 2003 ed. A. McWilliam and M. Rauch (Pasadena: Carnegie Observatories, http://www.ociw.edu/ociw/symposia/series/symposium4/proceedings.html)

More information

Using Photometric Data to Derive an HR Diagram for a Star Cluster

Using Photometric Data to Derive an HR Diagram for a Star Cluster Using Photometric Data to Derive an HR Diagram for a Star Cluster In In this Activity, we will investigate: 1. How to use photometric data for an open cluster to derive an H-R Diagram for the stars and

More information

12-3. Spherical groups of millions of stars found in the Milky Way are called: a) novas b) globular clusters X c) open clusters d) galactic clusters

12-3. Spherical groups of millions of stars found in the Milky Way are called: a) novas b) globular clusters X c) open clusters d) galactic clusters Chapter 12 Quiz, Nov. 28, 2012, Astro 162, Section 4 12-1. Where in our Galaxy has a supermassive (or galactic) black hole been observed? a) at the outer edge of the nuclear bulge b) in the nucleus X c)

More information

Lecture 7 Formation of the Solar System. Nebular Theory. Origin of the Solar System. Origin of the Solar System. The Solar Nebula

Lecture 7 Formation of the Solar System. Nebular Theory. Origin of the Solar System. Origin of the Solar System. The Solar Nebula Origin of the Solar System Lecture 7 Formation of the Solar System Reading: Chapter 9 Quiz#2 Today: Lecture 60 minutes, then quiz 20 minutes. Homework#1 will be returned on Thursday. Our theory must explain

More information

Today. Kirchoff s Laws. Emission and Absorption. Stellar Spectra & Composition

Today. Kirchoff s Laws. Emission and Absorption. Stellar Spectra & Composition Today Kirchoff s Laws Emission and Absorption Stellar Spectra & Composition 1 Three basic types of spectra Continuous Spectrum Intensity Emission Line Spectrum Absorption Line Spectrum Wavelength Spectra

More information

Astro Lecture 15. Light and Matter (Cont d) 23/02/09 Habbal_Astro Lecture 15

Astro Lecture 15. Light and Matter (Cont d) 23/02/09 Habbal_Astro Lecture 15 Astro110-01 Lecture 15 Light and Matter (Cont d) 1 What have we learned? Three basic types of spectra continuous spectrum emission line spectrum absorption line spectrum Light tells us what things are

More information

COMPARISON OF GAS AND DUST COOLING RATES IN NEARBY GALAXIES

COMPARISON OF GAS AND DUST COOLING RATES IN NEARBY GALAXIES IC 10 Henize 2-10 NGC 253 COMPARISON OF GAS AND DUST COOLING RATES IN NEARBY GALAXIES E.Bayet: LRA-LERMA-ENS (Paris) Antennae IC 342 M 83 NGC 6946 INTRODUCTION : OBJECTS : warm and dense molecular clouds

More information

Nuclear fusion in stars. Collapse of primordial density fluctuations into galaxies and stars, nucleosynthesis in stars

Nuclear fusion in stars. Collapse of primordial density fluctuations into galaxies and stars, nucleosynthesis in stars Nuclear fusion in stars Collapse of primordial density fluctuations into galaxies and stars, nucleosynthesis in stars The origin of structure in the Universe Until the time of formation of protogalaxies,

More information

Summary: Four Major Features of our Solar System

Summary: Four Major Features of our Solar System Summary: Four Major Features of our Solar System How did the solar system form? According to the nebular theory, our solar system formed from the gravitational collapse of a giant cloud of interstellar

More information

Chapter Pearson Education, Inc. Chapter Pearson Education, Inc. Chapter 19-22

Chapter Pearson Education, Inc. Chapter Pearson Education, Inc. Chapter 19-22 Suppose you tried to determine where we are in the galaxy by looking in different directions to see how many stars you could see. If you did this, you would pinpoint our location Suppose you tried to determine

More information

Galactic Chemical Evolution. Ena Choi

Galactic Chemical Evolution. Ena Choi Galactic Chemical Evolution Ena Choi Contents Introduction Formation and evolution of the Milky Way Galactic Halo Galactic Disk Cosmic Chemical Evolution References Introduction Simple chemical evolution

More information