W. van Altena IAU August 2009
Astrometry in the 21Astrometry in the 21stst Century: Century:Foundations for AstrophysicsFoundations for Astrophysics
William van Altena, editorYale University
29 chapters - 28 co-authorsfrom 13 countries
W. van Altena IAU August 2009
W. van Altena IAU August 2009
Micro-arcsecond Astrometry:How did we get there?
• Hipparcos awakened the world to the scientificpotential of milli-arcsecond astrometry– Stellar structure & evolution, local galactic
structure and kinematics• VERA & VLBA showed us that micro-arcsecond
radio astrometry can be done– Distance to the Orion cluster, proper motions in
jets• Gaia & SIM have excited us with the
possibility of micro-arcsecond opticalastrometry– Galactic structure and kinematics on a grand
scale– Definitive cosmological distance scales– Masses of exoplanets
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An Introduction to Astrometry:An Introduction to Astrometry:Foundations for AstrophysicsFoundations for Astrophysics
• Broad introduction to the fields to provide a basis for:– More specialized courses, where available– Follow-on self study by students when no other courses exist– Advanced international workshops on specialized topics– International summer research programs at institutes with
specializations in astrometry and celestial mechanics• Scaled to a 40-hour lecture course, but easily revised to other
standards like a 20-hour course by:– Reducing the depth covered in each section, or– Selectively omitting some subject areas
• Relative stress on subject areas will have to be adjusted to meetthe special needs of different institutions
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What still needs to be addressed?What still needs to be addressed?• The audience
– Ph.D. versus Masters degree• Topic stress should probably vary
according to the endpoint degreedesired
• Training style– Lecture style course– Lecture plus observatory internship– Internships at institutes and
observatories– International Workshops on specific
topics• Course content
– Topics need to be revised by specialistsin each specific area
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Topic introductionsTopic introductions• Astrometry and Celestial Mechanics are small,
specialized fields– Astrometry should be taught in conjunction with
courses whose science is aided by astrometry andcelestial mechanics
• Stellar formation, structure and evolution• Solar and exo-planetary system discovery, formation,
structure and evolution• Galaxy formation, structure (kinematical, dynamical and
spatial) and evolution– Science introductions to each topic are critical to
motivating students
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Organization of text
• Section 1: Opportunities and challenges for Astrometry in the21st Century (3 hours)
• Section 2: Relativistic Foundations of Astrometry and CelestialMechanics (10 hours)
• Section 3: Observing through the Atmosphere (7 hours)
• Section 4: From detected photons to the Celestial Sphere (14hours)
• Section 5: Applications of Astrometry to Astronomical Topics(9 hours)
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Section 1: Opportunities and challenges forAstrometry in the 21st Century
• Opportunities and challenges forAstrometry in the 21st Century– Michael Perryman
• Astrometry satellites: past,present and future– Lennart Lindegren
•
• Ground-based opportunities forAstrometry– Norbert Zacharias
Gaia
Large Synoptic Survey Telescope
SIM
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Section 2: Relativistic Foundations of Astrometryand Celestial Mechanics
• Vectors in Astrometry, an introduction• Lennart Lindegren
• Relativistic foundations of Astrometryand Celestial Mechanics– Sergei Klioner
• Celestial Mechanics of the N-bodyproblem– Sergei Klioner
• Celestial Coordinate Systems andPositions– Nicole Capitaine & Magda Stavinschi
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Section 3: Observing through the Atmosphere
• The Earth’s atmosphere– Bill van Altena
• Atmospheric limits to positionalprecision– Bill van Altena
• Astrometry with ground-baseddiffraction-limited imaging– Andrea Ghez
• Optical Interferometry– Andreas Glindemann
• Radio Interferometry– Edward Fomalont
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Section 4: From detected photons to the CelestialSphere
• Geometrical Optics forAstrometry• Daniel Schroeder
• Imaging detectors– Steve Howell
• Time-delayed integration– David Rabinowitz
• Statistical Astrometry• Anthony Brown
• HST imaging astrometryand photometry– Jay Anderson
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Section 4: From detected photons to the CelestialSphere (continued)
• Image deconvolution– Jorge Nuñez
• From measures to celestialcoordinates• Zheng-Hong Tang & Terry Girard
• Astrometric Catalogs• Carlos López
• Trigonometric Parallaxes• Fritz Benedict
• Fundamental algorithms andparameters useful forAstrometry– Patrick Wallace
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Section 5: Applications of Astrometry toAstronomical Topics
• Galactic Structure &Kinematics• René Méndez
• Binary and MultipleStars– Elliott Horch
• Binaries: HST,Hipparcos and Gaia– Dimitri Pourbaix
• Star clusters– Imants Platais
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Section 5: Applications of Astrometry toAstronomical Topics (cont)
• Solar System astrometry– Francois Mignard
• Extra-solar planets– Alessandro Sozzetti
• Astrometric measurementsand Cosmology• Richard Easther
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Acknowledgements• Colleagues who provided us with many suggestions
for the one-semester syllabus in Astrometry andCelestial Mechanics:– Sergei Kopeikin, Sergei Klioner, Nicole Capitaine, Ana
Gomez, Wenjing Jin, Stephen Unwin, Elliott Horch,Michael Perryman, Catherine Turon, Michael Efroimsky,Kenneth Seidelmann, Steve Majewski and others
• NSF, NASA, ESA, & ESO, who provide us withoutstanding facilities for astrometric research.
ReferenceEducating astrometry and celestialmechanics students for the 21st centuryvan Altena, W. F., Stavinschi, M.van Altena, W. F., Stavinschi, M.IAU Symposium 248, Shanghai, October 2007.IAU Symposium 248, Shanghai, October 2007.
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