demonstration of vo tools and technology tamás budavári johns hopkins university
TRANSCRIPT
9/13/2004 NVO Summer School, Aspen 2004
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VO Tools
Direct access toImagesSpectraCatalogs
Higher levelCross matchetc.
9/13/2004 NVO Summer School, Aspen 2004
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SDSS Image Cutout
Build JPEG mosaicsFor given (RA, Dec)Arbitrary zoom levelsOverplot catalog dataOverplot geometryMapQuest like navigationList of objects
Web servicesJPEG returned in DIMEor byte array in XML Kudos to Maria
Nieto-Santisteban
Kudos to Maria Nieto-
Santisteban
9/13/2004 NVO Summer School, Aspen 2004
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Spectrum Services
Public repository500,000 spectra (2B row)
Spatial search and more
Register & submit yours
Web siteOn-the-fly plotting
Building composites
Web servicesMore options and tools
Kudos to László Dobos
Kudos to László Dobos
9/13/2004 NVO Summer School, Aspen 2004
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Bandpass Services
Public repositorySearch by keyword or eff
Extract in various formatsRegister & submit yours
Web siteOn-the-fly plottingEasy access to all
Web servicesTo code against
9/13/2004 NVO Summer School, Aspen 2004
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Catalog AccessU wanna talk database?
Structured Query Languageor SQL for short (standard)
Simple syntaxSELECTSELECT <columns> FROMFROM <table> WHEREWHERE <conditions>
For example: select ra, dec
from galaxy where r<19
What else do we need?
To specify area on sky• Could be very complicated
Standard interface to DBs
• XML Web Services for interop
Tools to federate archives
• Dynamically for flexibilityAstronomical Data Astronomical Data Query LanguageQuery Language
9/13/2004 NVO Summer School, Aspen 2004
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Open SkyQuery
SkyNode interface to archives
Implements ADQL returns VOTableBasic node understands “REGION”Full node understands “XMATCH”
SkyQuery portalKnows the SkyNodes from RegistryUnderstands federated query
http://openskyquery.net
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Summary
Direct access toImagesSpectraCatalogs
Higher levelCross matchetc.
Your project
Your project
herehereYour project
Your project
herehere
9/13/2004 NVO Summer School, Aspen 2004
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Project IdeasAverage QSO spectrum?
Composite spectrum of the 20 most distant SDSS quasars?Average spectrum as a function of redshift?
• Try a few redshift bins by hand this afternoon (pick ~10-20 objects for each bin)• Write code to analyze many more redshift bins (flat z histogram inside bin?)
Favorite object?Get image, spectrum and/or catalog data for your pet galaxy
• Don’t remember the coords? Try name resolver at http://voservices.net/ned/
Build a series of SDSS mosaic images • Get images of astronomical objects given by RA and Dec (or by name?)• Write code to make a movie zooming on any given galaxy (coords or name)
Your idea here…