Hot Stars as Targets for Intensity Interferometry. Hannes Jensen Lund Observatory, Sweden
|
|
- Alvin Roberts
- 5 years ago
- Views:
Transcription
1 Hot Stars as Targets for Intensity Interferometry Hannes Jensen Lund Observatory, Sweden
2 Aims Given recent progress in phase interferometry: which should be the prime observational targets for II? What is least difficult to observe? Starting point for observing programs, white papers, etc.
3 Selection Criteria What makes a target suitable for II? Bright High above background noise level, moonlight etc. Hot S/N improves greatly with target temperature Astronomically interesting Features on a (sub)milliarcsecond level. Deformation due to rapid rotation, pulsation, disks, winds, etc.
4 The Bright Star Catalogue The Bright Star Catalogue contains the ~9000 brightest stars.
5 Temperatures Effective temperatures were approximated with a polynomial fit to values from [Bessel et al, 1998, A&A333]. ~2600 objects are hotter than 9000 K and brighter than V=7
6 Final selection 34 stars exist with (Teff > 9000 K V < 2) Teff > K A few other interesting objects were added Angular diameters from the CHARM2 compilation. [Richichi et al., 2005, A&A431, 773]
7 Selected objects Temperature vs. apparent magnitude of selected stars. Circle size indicates angular diameter where available. 1 mas
8 List of Objects Name Angular size (mas) Rot. vel. * [km/s] Spec. class Teff [K] V [mag] Notes Achernar, HR B3Ve High rotational velocity, Be-star Rigel, HR B8Iab Emission line star, SN candidate Lambda Lep, HR B0.5IV Bellatrix, HR B2III Variable star Elnath, HR B7III Star in double system HR B0V Variable star HR B0.5V Star in double system Alnilam A, HR B0Iab Emission line star HR O9.5V High rotational velocity Beta CMa B1II/III Short period beta Cep variable Alhena, HR A0IV Star in double system S Mon, HR O7Ve Sirius, HR A1V Bright, well studied, high angular size EZ CMa, HR 2583? WN Highly variable W-R star Adara, HR B2Iab Star in double system Naos, HR O5Ia BY Dra variable, high rot. vel. HR WCv Double or multiple star HR A2IV * vrot sin i
9 List of Objects, contd. Name Angular size (mas) Rot. vel. [km/ s] Spec. class Teff [K] V [mag] Notes Beta Cen, HR B1III Beta Cep variable Tau Sco, HR B0.2V Lambda Sco, HR B2IV Beta Cep variable Kaus Austr., HR B9.5III Star in double system Vega, HR ? A0V Bright, well studied Peacock, HR B2IV Spectroscopic binary Deneb, HR A2Iae Alpha Cyg variable HR B6V High rotational velocity Fomalhaut, HR A4V First optically imaged exo-planet Eta Car, HR (CSS)? pec Highly unstable, SN candidate? WD ? Hottest WD known Gamma Vel, HR WC8+O9I 1.8 WR-O binary Regulus, HR B7V High rotational velocity Acrux, HR B0.5IV Spectroscopic binary HR B1V High rotational velocity Beta Cru, HR B0.5IV Beta Cep variable Eps UMa, HR A0p Variable star Spica, HR B1III-IV High rotational velocity, variable Alcaid, HR 5191 < B3V High rotational velocity, variable
10 Selected objects
11 Achernar (B3Ve) Very rapidly rotating Be-star Highly deformed due to rotation, observed with VLTI [de Souza et al., 2003, A&A407, 47] Teff K V [mag] 0.46 v sin i 250 km/s θ 1.85 mas Complex stellar winds due to rotation [e.g., Kervella et al., 2008] Circumstellar disk may be studied with II in its Hα emission Companion star suggested [Kervella & de Souza, 2007, A&A474, 49] [Kanaan et al., 2008, A&A, 486]
12 Rigel (B8Iab) The nearest blue supergiant Nearest type II supernova progenitor? [Stewart et al., 2009] Teff K V [mag] 0.12 v sin i 30 km/s θ 2.4 mas Periodic oscillations on many timescales [Stewart et al., 2009] Variation in absorption/emission in Hα lines [Morrison et al., 2009]
13 β Centauri (B1III) Teff K* The brightest β Cep variable Oscillations, line profile variations Highly complex spectroscopic binary, both components variable [Ausseloos et al., 2006, A&A455] V [mag] 0.61 v sin i θ 140 km/s 0.9 mas *both components approx. equal mass and temp. A challenge for current evolution scenarios in close binaries [Ausseloos et al., 2002 A&A209] Orbits measured with Sydney University Stellar Interferometer (SUSI) [Davis et al, 2005,MNRAS ]
14 Vega (A0 V) Widely studied standard star. Arguably the second most important star in the sky after the Sun [Gulliver et al., 94, ApJ429] Teff K V [mag] 0.03 v sin i 15 km/s θ 3.2 mas Realized to be a rapidly rotating pole-on star Center-limb intensities: 18x drop at 500 nm, compared to 5x drop for non-rotating model [Peterson et al., 2006, Nature 440, 896]
15 Fomalhaut (A4V) Host star of an optically imaged exoplanet Debris disk with planet(s) Teff K V [mag] 1.16 v sin i 100 km/s θ 2 mas
16 η Carinae Most luminous star known in the Galaxy Highly unstable, doomed to explode within years Imaged with HST and VLT to some 0.1 arcsec; Teff K V [mag] 6.21 v sin i? θ 5 mas* * Circumstellar shell VLTI data to milliarcsecond level shows asymmetries in winds due to rapid rotation [Weigelt et al., 2007, A&A, 464, 87] Images: eso.org
17 γ 2 Velorum (WC8+O9I) Closest and brightest Wolf-Rayet star. WR-O binary, important for understanding stellar evolution [North et al., 2007, MNRAS 377] Teff K V [mag] 1.8 v sin i? θ 0.4 mas Excellent system for studying massive stars and their interacting winds [Millour et al., 2007, A&A464] Already observed at Narrabri by Hanbury Brown et al.: Angular size in C III-IV emission at 465 nm shows stellar envelope five times larger than stellar disk in the continuum
18 Conclusions Observationally suitable and exciting targets exist all over the sky Much to be gained from sub-milliarcsecond measurements - way more than just stellar diameters!
Astron 104 Laboratory #9 The H-R Diagram
Name: Date: Section: Astron 104 Laboratory #9 The H-R Diagram Section 10.1, 10.5 If we know the temperature of a star (or its Spectral Type) and the stars intrinsic brightness (or luminosity), a great
More informationAstron 104 Laboratory #8 The H-R Diagram
Name: Date: Section: Astron 104 Laboratory #8 The H-R Diagram Section 10.1, 10.5 Introduction The Hertzsprung-Russell diagram, or H-R diagram for short, relates two fundamental properties of stars and
More informationThe Hertzsprung - Russell Diagram Laboratory 11
The Hertzsprung - Russell Diagram Laboratory 11 Objective: In this laboratory a random sample of stars will be used to create a HR Diagram. From the diagram it will be determined which category certain
More informationHR Diagram Lab. Area 1 Area 4. Area 5. Area 2. Area 6 Area 3
Name / 65 pts HR Diagram Lab Introduction Some of the greatest advances concerning the nature of stars have come about by comparing their properties using graphs. In the early 1900 s, while studying the
More informationCepheids and Gaia's second data release
The CHARA Array Science Meeting 208 Cepheids and Gaia's second data release Pierre Kervella LESIA, Paris Observatory A. Mérand, A. Gallenne, B. Trahin, S. Borgniet, N. Nardetto, V. Hocdé, R. I. Anderson,
More informationScience Opportunities in Stellar Physics. Douglas R. Gies CHARA, Georgia State Univ., and the Stellar Physics Working Group
Science Opportunities in Stellar Physics Douglas R. Gies CHARA, Georgia State Univ., gies@chara.gsu.edu and the Stellar Physics Working Group General Themes! Fundamental properties! Interior structure
More informationHOMEWORK - Chapter 17 The Stars
Astronomy 20 HOMEWORK - Chapter 7 The Stars Use a calculator whenever necessary. For full credit, always show your work and explain how you got your answer in full, complete sentences on a separate sheet
More informationThe science potential of atmospheric Cherenkov arrays used as intensity interferometers
The science potential of atmospheric Cherenkov arrays used as intensity interferometers Michael Daniel for Willem-Jan de Wit w.j.m.dewit@leeds.ac.uk Atmospheric Cherenkov Telescope Arrays Multiple telescopes
More informationThe Hertzprung-Russell (HR) Diagram
Name: Partner(s): 1102 or 3311: Desk # Date: The Hertzprung-Russell (HR) Diagram Purpose Reproduce Hertzsprung s and Russell s simultaneous discovery Investigate the relationships between luminosity, mass,
More informationMy God, it s full of stars! AST 248
My God, it s full of stars! AST 248 N * The number of stars in the Galaxy N = N * f s f p n h f l f i f c L/T The Galaxy M31, the Andromeda Galaxy 2 million light years from Earth The Shape of the Galaxy
More informationStars 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 informationThe Sun and the Stars
Classification of stellar spectra Potted History : 1802 William Wallaston showed that the spectrum of the sun is not simply a continuous spectrum, but is broken up by a series of dark lines (absorption
More informationAstronomy 100 Spring 2006 Lecture Questions Twelve Weeks Review
Astronomy 100 Spring 2006 Lecture Questions Twelve Weeks Review 16-1 Fusion in the Sun The solar corona has temperatures roughly the same as temperatures in the Sun's core, where nuclear fusion takes place.
More informationBasic 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 informationTHE STARS. Information and contacts: -
THE STARS G. Iafrate (a), M. Ramella (a) and V. Bologna (b) (a) INAF - Astronomical Observatory of Trieste (b) Istituto Comprensivo S. Giovanni Sc. Sec. di primo grado M. Codermatz" - Trieste Information
More informationFriday, March 21, 2014 Reading for Exam 3: End of Section 6.6 (Type Ia binary evolution), 6.7 (radioactive decay), Chapter 7 (SN 1987A), NOT Chapter
Friday, March 21, 2014 Reading for Exam 3: End of Section 6.6 (Type Ia binary evolution), 6.7 (radioactive decay), Chapter 7 (SN 1987A), NOT Chapter 8 (Neutron Stars), keep for Exam 4. Background: Sections
More informationMass-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 informationInterferometric Constraints on Fundamental Stellar Parameters
Interferometric Constraints on Fundamental Stellar Parameters Pierre Kervella LESIA, Paris Observatory photo: S. Guisard Heat Heat Transport Heat Transport Photosphere Radiation Heat Transport Photosphere
More informationSearching for Other Worlds
Searching for Other Worlds Lecture 32 1 In-Class Question What is the Greenhouse effect? a) Optical light from the Sun is reflected into space while infrared light passes through the atmosphere and heats
More informationObserving Stellar Evolution Observing List
Observing Stellar Evolution Observing List Bill Pellerin, Houston Astronomical Society This list is organized by category of object. Within each category, the list is sorted by RA to help you plan your
More informationStars. For Jupiter: M/Msun = 0.001
Stars Stars are classified by spectral classes O,B,A,F,G,K,M Oh be a fine girl (or guy), kiss me! Key here is the effective temperature of the star (surface temperature) Difference in spectrum is due to
More informationAstronomy 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 informationY Centauri A 6. Alpha O Centauri B 7. Alpha
H-R Star Spectrum Lab The H-R diagram, as it s known for short, plots a star s luminosity its true brightness against its surface temperature in Kelvin. Are there patterns that emerge and what does this
More informationH-R Diagram Lab. Vocabulary:
H-R Diagram Lab Vocabulary: luminosity: brightness dependent on a star s size; temperature and distance spectral class: classification of stars by their spectrum and luminosity magnitude: measure of the
More information10/29/2009. The Lives And Deaths of Stars. My Office Hours: Tuesday 3:30 PM - 4:30 PM 206 Keen Building. Stellar Evolution
of s Like s of Other Stellar The Lives And Deaths of s a Sun-like s More 10/29/2009 My Office Hours: Tuesday 3:30 PM - 4:30 PM 206 Keen Building Test 2: 11/05/2009 of s Like s of Other a Sun-like s More
More informationNames: Team: Team Number:
Astronomy C Michigan Region 8 March 11, 2017 Names: Team: Team Number: Directions 1. There is a separate answer sheet. Answers written elsewhere (e.g. on the test) will not be considered. 2. You may take
More informationEach star is born with a specific mass. This mass is the main factor in determining the star s brightness, temperature, expected lifetime, type of
Each star is born with a specific mass. This mass is the main factor in determining the star s brightness, temperature, expected lifetime, type of death, and spectra. Stars are classified according to
More informationLAB: Star Classification
Name: LAB: Star Classification INTRODUCTION: Like most scientists, astronomers like to categorize the Universe around them, and stars are no exception. Here s how astronomers classify stars into different
More informationMajor Stars of the Orion Constellation
Major Stars of the Orion Constellation By Mervyn Millward Looking north and gazing up at the sky on a Tasmanian summer evening, one can easily pick out the famous Orion (The Hunter) constellation. From
More informationReview Questions for the new topics that will be on the Final Exam
Review Questions for the new topics that will be on the Final Exam Be sure to review the lecture-tutorials and the material we covered on the first three exams. How does speed differ from velocity? Give
More informationBinary Evolution Novae, Supernovae, and X-ray Sources
Binary Evolution Novae, Supernovae, and X-ray Sources The Algol Mystery Algol is a double-lined eclipsing binary system with a period of about 3 days (very short). The two stars are: Star A: B8, 3.4M o
More informationLecture 8: Stellar evolution II: Massive stars
Lecture 8: Stellar evolution II: Massive stars Senior Astrophysics 2018-03-27 Senior Astrophysics Lecture 8: Stellar evolution II: Massive stars 2018-03-27 1 / 29 Outline 1 Stellar models 2 Convection
More informationWhat is a star? A body of gases that gives off tremendous amounts of energy in the form of light & heat. What star is closest to the earth?
Stars What is a star? A body of gases that gives off tremendous amounts of energy in the form of light & heat. What star is closest to the earth? Answer: The SUN It s about 150,000,000 km from earth =
More informationLife and Evolution of a Massive Star. M ~ 25 M Sun
Life and Evolution of a Massive Star M ~ 25 M Sun Birth in a Giant Molecular Cloud Main Sequence Post-Main Sequence Death The Main Sequence Stars burn H in their cores via the CNO cycle About 90% of a
More informationGALAXIES 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 informationChapter 12 Stellar Evolution
Chapter 12 Stellar Evolution Guidepost Stars form from the interstellar medium and reach stability fusing hydrogen in their cores. This chapter is about the long, stable middle age of stars on the main
More informationChapter 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 informationChapter 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 informationAstro 101 Fall 2013 Lecture 8. T. Howard
Astro 101 Fall 2013 Lecture 8 T. Howard Measuring the Stars How big are stars? How far away? How luminous? How hot? How old & how much longer to live? Chemical composition? How are they moving? Are they
More informationGet 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 informationAstroparticle Physics
Astroparticle Physics 43 (2013) 331 347 Contents lists available at SciVerse ScienceDirect Astroparticle Physics journal homepage: www.elsevier.com/locate/astropart Optical intensity interferometry with
More informationExoplanets Direct imaging. Direct method of exoplanet detection. Direct imaging: observational challenges
Black body flux (in units 10-26 W m -2 Hz -1 ) of some Solar System bodies as seen from 10 pc. A putative hot Jupiter is also shown. The planets have two peaks in their spectra. The short-wavelength peak
More informationCharacterizing Stars
Characterizing Stars 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
More information5. 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 informationMagnitudes. How Powerful Are the Stars? Luminosities of Different Stars
How Powerful Are the Stars? Some stars are more powerful than others Power is energy output per. (Example: 00 Watts = 00 joules per second) Astronomers measure the power, or brightness of stars in ways:
More information18. Which graph best represents the relationship between the number of sunspots and the amount of magnetic activity in the Sun?
1. Which star has a surface temperature most similar to the surface temperature of Alpha Centauri? A) Polaris B) Betelgeuse C) Procyon B D) Sirius 2. Giant stars have greater luminosity than our sun mainly
More informationAstro Fall 2012 Lecture 8. T. Howard
Astro 101 003 Fall 2012 Lecture 8 T. Howard Measuring the Stars How big are stars? How far away? How luminous? How hot? How old & how much longer to live? Chemical composition? How are they moving? Are
More informationPhys 100 Astronomy (Dr. Ilias Fernini) Review Questions for Chapter 9
Phys 0 Astronomy (Dr. Ilias Fernini) Review Questions for Chapter 9 MULTIPLE CHOICE 1. We know that giant stars are larger in diameter than the sun because * a. they are more luminous but have about the
More informationGalaxies and Stars. 3. Base your answer to the following question on The reaction below represents an energy-producing process.
Galaxies and Stars 1. To an observer on Earth, the Sun appears brighter than the star Rigel because the Sun is A) hotter than Rigel B) more luminous than Rigel C) closer than Rigel D) larger than Rigel
More informationWhat do the Roman numerals mean and how do stars die
What do the Roman numerals mean and how do stars die What is luminosity? Luminosity is the energy emitted from a star, or basically how bright it is compared to our Sun The higher the luminosity, the higher
More informationGoal - to understand what makes supernovae shine (Section 6.7).
Wednesday, March 11, 2015 (Class Friday) Reading for Exam 3: Chapter 6, end of Section 6 (binary evolution), Section 6.7 (radioactive decay), Chapter 7 (SN 1987A) Background in Chapters 3, 4, 5. Background:
More informationAstronomy Ch. 20 Stellar Evolution. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
Name: Period: Date: Astronomy Ch. 20 Stellar Evolution MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A star (no matter what its mass) spends
More informationAstronomy Ch. 20 Stellar Evolution. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
Name: Period: Date: Astronomy Ch. 20 Stellar Evolution MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A star (no matter what its mass) spends
More informationPhotoionized winds of cool stars
Photoionized winds of cool stars Jonathan Mackey Argelander-Institut für Astronomie (aifa), Uni. Bonn Collaborators:! Shazrene Mohamed!(SAAO, Cape Town)! Vasilii Gvaramadze! (Lomonosov Moscow State University,
More informationChapter 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 informationChapter 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 informationStars, 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 informationThis class: Life cycle of high mass stars Supernovae Neutron stars, pulsars, pulsar wind nebulae, magnetars Quark-nova stars Gamma-ray bursts (GRBs)
This class: Life cycle of high mass stars Supernovae Neutron stars, pulsars, pulsar wind nebulae, magnetars Quark-nova stars Gamma-ray bursts (GRBs)!1 Cas$A$ All$Image$&$video$credits:$Chandra$X7ray$ Observatory$
More informationThe Correlation Between Stellar Radii and the Masses of Stable Atomic Nuclei
The Correlation Between Stellar Radii and the Masses of Stable Atomic Nuclei B. F. Riley In an analysis motivated by the AdS/CFT correspondence, the radii of nearby stars, including the sun, are shown
More information1. 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 informationRømer Science Mission Plan
Institute of Physics and Astronomy, University of Aarhus Rømer Science Mission Plan Danish Small Satellite Programme Document No.(issue): MONS/IFA/MAN/PLN/0001(1) Date: 2001-05-29 Prepared by: Jørgen Christensen-Dalsgaard,
More informationDistances 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 informationTest #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 informationASTR-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 informationHubble Science Briefing: 25 Years of Seeing Stars with the Hubble Space Telescope. March 5, 2015 Dr. Rachel Osten Dr. Alex Fullerton Dr.
Hubble Science Briefing: 25 Years of Seeing Stars with the Hubble Space Telescope March 5, 2015 Dr. Rachel Osten Dr. Alex Fullerton Dr. Jay Anderson Hubble s Insight into the Lives of Stars Comes From:
More informationLecture 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 informationMarian Physics! Apparent Magnitude. Flat Prairie Publishing
Marian Physics! Apparent Flat Prairie Publishing Apparent Assignment Apparent Apparent The scale used in astronomy to measure the brightness of stars is steeped in history and perhaps not a whole lot of
More informationVariable Stars South. Who we are What we do. 2
Who we are What we do www.variablestarssouth.org 2 We are a group of amateur astronomers. Mainly from Australia New Zealand with a few from other parts of the globe We study stars that vary in brightness
More informationSpectroscopy, the Doppler Shift and Masses of Binary Stars
Doppler Shift At each point the emitter is at the center of a circular wavefront extending out from its present location. Spectroscopy, the Doppler Shift and Masses of Binary Stars http://apod.nasa.gov/apod/astropix.html
More informationReview 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 informationFirst Scientific Results from the VLT Interferometer*
First Scientific Results from the VLT Interferometer* Francesco Paresce, Roy Van Boekel, Serge Correia, Emmanuel Di Folco, Andreas Glindemann, Pierre Kervella, Andrea Richichi, Markus Schoeller, Massimo
More informationStars 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 informationAstar s most important attributes are its mass, temperature, radius, composition, and rate of rotation. The Sun, for
T.A. Pauls 1 and D.M. Peterson 2 1 Remote Sensing Division 2 Stony Brook University Vega is a Rapidly Rotating Star Astar s most important attributes are its mass, temperature, radius, composition, and
More informationThe Sun (chapter 14) some of this is review from quiz 3, but you should
Astro20 / Harpell Topics for Quiz 4 The quiz will have 20 multiple choice questions; several "fill in the blanks" about five short essay questions that may require sketches.. If you can answer everything
More informationEndpoints of Stellar Evolution. Dicy Saylor ASTR 8000 Nov 19, 2014
Endpoints of Stellar Evolution Dicy Saylor ASTR 8000 Nov 19, 2014 Overview White Dwarfs PNNe, White Dwarfs, and PG1159, oh my! Novae Classical Novae and Cataclysmic Variables Supernovae Type I and Type
More informationRecent results from VEGA Perspective of a 6T visible combiner
Recent results from VEGA Perspective of a 6T visible combiner Denis Mourard O. Creevey, N.Nardetto, K. Perraut And the VEGA group 2014 Statistics 17 proposals (13 from Nice, 3 from Grenoble, 1 from Paris)
More informationThe Binary System VV Cephei Eclipse Campaign 2017/2019 OHP-Meeting July 2017
The Binary System VV Cephei Eclipse Campaign 2017/2019 OHP-Meeting July 2017 Ernst Pollmann International Working Group Active Spectroscopy in Astronomy http://astrospectroscopy.de 3 One of the best known
More informationOther planetary systems
Exoplanets are faint! Other planetary systems Planets are seen only by reflected light at optical wavelengths At the distance of another star the faint light of a planet is lost in the glare of the star
More informationThe HR Diagram: A Laboratory Exercise
Pisgah Astronomical Research Institute 2009 The HR Diagram: A Laboratory Exercise The HR Diagram Lab gives students the opportunity to construct an HR Diagram based on their own classifications of 119
More informationBinary Evolution Novae, Supernovae, and X-ray Sources
Binary Evolution Novae, Supernovae, and X-ray Sources http://apod.nasa.gov/apod/ http://www.space.com/32150-farthest-galaxy-smashes-cosmic-distance-record.html The Algol Mystery Algol is a double-lined
More informationExoplanets Direct imaging. Direct method of exoplanet detection. Direct imaging: observational challenges
Black body flux (in units 10-26 W m -2 Hz -1 ) of some Solar System bodies as seen from 10 pc. A putative hot Jupiter is also shown. The planets have two peaks in their spectra. The short-wavelength peak
More informationInternational Journal of Scientific & Engineering Research Volume 8, Issue 5, May ISSN
International Journal of Scientific & Engineering Research Volume 8, Issue 5, May-2017 322 Reassessment of the old but still employed theories of Universe through database checking Author: Weitter Duckss
More informationAccurate Mass Determination of the Old White Dwarf G through Astrometric Microlensing
Hubble Space Telescope Cycle 19 GO Proposal 871 Accurate Mass Determination of the Old White Dwarf G105-30 through Astrometric Microlensing Principal Investigator: Dr. Kailash C. Sahu Institution: Space
More informationPosition 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 informationSpectral Classification of Stars
Department of Physics and Geology Spectral Classification of Stars Astronomy 1402 Part 1: Background Spectral Classification of Stars 1.1 Spectral Types: O, B, A, F, G, K, M On a dark, clear night far
More information15.1 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 informationThe cosmic distance scale
The cosmic distance scale Distance information is often crucial to understand the physics of astrophysical objects. This requires knowing the basic properties of such an object, like its size, its environment,
More informationDaily Science 04/04/2017
Daily Science 04/04/2017 Which statement best describes the difference between type A stars and type B stars as shown in the diagram? a. Type A stars burn for a shorter amount of time than type B stars.
More informationSection 8. How bright? Magnitudes and Telescopes 1
Section 8. How bright? Magnitudes and Telescopes 1 More than 2000 years ago, the Greek astronomer Hipparchus put together the first star catalog (as far as we know). Since he wanted to indicate somehow
More information1 of 6 5/2/2015 6:12 PM
1 of 6 5/2/2015 6:12 PM 1. What is parallax? The distance to an object, measured in parsecs. The difference between the apparent and absolute magnitude. The apparent shift in POSITION of an object caused
More informationLECTURE 15: WHITE DWARFS AND THE ADVANCED EVOLUTION OF MASSIVE STARS.
LECTURE 15: WHITE DWARFS AND THE ADVANCED EVOLUTION OF MASSIVE STARS http://apod.nasa.gov/apod/astropix.html White Dwarfs Low mass stars are unable to reach high enough temperatures to ignite elements
More informationHomework 2 AST 301, Sections and 46850, Spring NAME Student EID Score: on last page. Due Tuesday, March 1, 2016
Homework 2 AST 301, Sections 46845 and 46850, Spring 2016 NAME Student EID Score: on last page Due Tuesday, March 1, 2016 Questions A C should help you to understand the properties of light. Show your
More informationChapter 12 Stellar Evolution
Chapter 12 Stellar Evolution Guidepost This chapter is the heart of any discussion of astronomy. Previous chapters showed how astronomers make observations with telescopes and how they analyze their observations
More informationVV Cephei Eclipse Campaign 2017/19
VV Cephei Eclipse Campaign 2017/19 Jeffrey L. Hopkins (187283) Hopkins Phoenix Observatory 7812 West Clayton Drive, Phoenix, Arizona USA phxjeff@hposoft.com Philip D. Bennett Department of Astronomy &
More informationMeasuring the Stars. Chapter 10. Chapters 17, 19, 18
Measuring the Stars Chapter 10 Chapters 17, 19, 18 1 2 3 Bessel Hipparcos 4 Lecture-Tutorial on Parallax and the Parsec p 37 6) Consider two stars (C and D) that both exhibit parallax. If C appears to
More informationPr 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 informationDiscovery of a New Gamma-Ray Binary: 1FGL J
Discovery of a New Gamma-Ray Binary: 1FGL J1018.6-5856 Robin Corbet (UMBC/NASA GSFC) on behalf of the Fermi-LAT collaboration, & M.J. Coe, P.G. Edwards, M.D. Filipovic, J.L. Payne, J. Stevens, M.A.P. Torres
More informationPage # Astronomical Distances. Lecture 2. Astronomical Distances. Cosmic Distance Ladder. Distance Methods. Size of Earth
Size of Astronomical istances ecture 2 Astronomical istances istance to the Moon (1 sec) istance to the Sun (8 min) istance to other stars (years) istance to centre of our Galaxy ( 30,000 yr to centre)
More informationThe Evening Sky in February 2017
The Evening Sky in February 2017 Brilliant Venus is the 'evening star', appearing due west soon after sunset. It sets progressively earlier: 90 minutes after the sun at the beginning of the month, shrinking
More informationDistribution of X-ray binary stars in the Galaxy (RXTE) High-Energy Astrophysics Lecture 8: Accretion and jets in binary stars
High-Energy Astrophysics Lecture 8: Accretion and jets in binary stars Distribution of X-ray binary stars in the Galaxy (RXTE) Robert Laing Primary Compact accreting binary systems Compact star WD NS BH
More information