theory in the virtual observatory gerard lemson, gavo
TRANSCRIPT
Theory in the Theory in the Virtual ObservatoryVirtual Observatory
Gerard Lemson, GAVOGerard Lemson, GAVO
2005-06-302005-06-30 RingbergRingberg, Gerard Lemson, Gerard Lemson
The VOThe VO Broad goalBroad goal
Make results of astronomical research, data Make results of astronomical research, data and and applications, more readily applications, more readily available to larger community, and create value-adding services. available to larger community, and create value-adding services.
Facilitate:Facilitate: communication of resultscommunication of results checking of resultschecking of results use of resultsuse of results comparison of different resultscomparison of different results combination of different results to create new onescombination of different results to create new ones
ThroughThrough online availability of datasets and applicationsonline availability of datasets and applications standardized publication and discovery mechanismsstandardized publication and discovery mechanisms standardized description (meta-data, FITS++)standardized description (meta-data, FITS++) standardized selection mechanismsstandardized selection mechanisms standardized form(at)s of standardized form(at)s of transmittedtransmitted data data value added servicesvalue added services
Why ?Why ?
2005-06-302005-06-30 RingbergRingberg, Gerard Lemson, Gerard Lemson
SDSS
ROSAT
2MASS
FIRST GAIA
2005-06-302005-06-30 RingbergRingberg, Gerard Lemson, Gerard Lemson
ROSATFIRST GAIA
SDSS2MASS
2005-06-302005-06-30 RingbergRingberg, Gerard Lemson, Gerard Lemson
RegistryRegistry publicationpublication discoverydiscovery
Data modelsData models description (UCD)description (UCD)
Query protocolsQuery protocols selection (selection (cone searchcone search, ADQL), ADQL) combination (XMatch)combination (XMatch)
Data access protocolsData access protocols retrieval (VOTable)retrieval (VOTable)
ApplicationsApplications user interfaces (Aladin)user interfaces (Aladin) visualisation (VOPlot)visualisation (VOPlot) analysis (…)analysis (…)
2005-06-302005-06-30 RingbergRingberg, Gerard Lemson, Gerard Lemson
TheoryTheory Existing protocols not applicableExisting protocols not applicable
Position based queriesPosition based queries Combination of different archives less obviousCombination of different archives less obvious
Data models insufficientData models insufficient New “observables”New “observables” Different “provenance”Different “provenance” Different characterizationDifferent characterization More complex data structuresMore complex data structures
Less well developed history of archivingLess well developed history of archiving No FITS for simulationsNo FITS for simulations
New use casesNew use cases Theorists : data mining simulation resultsTheorists : data mining simulation results Observers : virtual telescopeObservers : virtual telescope
2005-06-302005-06-30 RingbergRingberg, Gerard Lemson, Gerard Lemson
Archiving of simulationsArchiving of simulations
Use relational databaseUse relational database GalICS GalICS SDSSSDSS
Halo merger trees from milli-MillenniumHalo merger trees from milli-Millennium data model for treesdata model for trees
SAM galaxy cataloguesSAM galaxy catalogues links to haloslinks to halos add merger treesadd merger trees
SQL query interface SQL query interface http://www.g-vo.org/mpasims (Springel, Croton, Blaizot)http://www.g-vo.org/mpasims (Springel, Croton, Blaizot)
Soon: add dynamic SAM to interfaceSoon: add dynamic SAM to interface
2005-06-302005-06-30 RingbergRingberg, Gerard Lemson, Gerard Lemson
Observed
Simulated
Thanks to Alexis Finoguenov, Ulrich Briel, Peter Schuecker, MPE)
Thanks to Volker Springel
Virtual TelescopeVirtual Telescope
2005-06-302005-06-30 RingbergRingberg, Gerard Lemson, Gerard Lemson
Virtual TelescopeVirtual Telescope
Use simulations for help in interpreting Use simulations for help in interpreting observations (e.g. Peter Schneider for this observations (e.g. Peter Schneider for this morning)morning)
Bring simulations into “observational plane”Bring simulations into “observational plane” Create results similar to observationsCreate results similar to observations Can be analysed with same techniques as Can be analysed with same techniques as
observationsobservations Can be compared “directly” to obs-s\Can be compared “directly” to obs-s\
Use cases:Use cases: Check observational biases using realistic modelsCheck observational biases using realistic models Survey/observation planningSurvey/observation planning Check models to observationsCheck models to observations
2005-06-302005-06-30 RingbergRingberg, Gerard Lemson, Gerard Lemson
PrototypesPrototypes
VisualisationVisualisation SmacSmac (Dolag) (Dolag) MoMaFMoMaF (Blaizot) (Blaizot)
Virtual telescopeVirtual telescope http://www.g-vo.org/planckhttp://www.g-vo.org/planck
2005-06-302005-06-30 RingbergRingberg, Gerard Lemson, Gerard Lemson
Interoperability: Interoperability: Virtual telescope configurationVirtual telescope configuration
ComponentsComponents simulationssimulations telescope modelstelescope models foregrounds (incl. lensing)foregrounds (incl. lensing)
SpecificationSpecification ““pre-observation image”pre-observation image” interfacesinterfaces workflowworkflow
Implementations …Implementations …
Virtual telescope Virtual telescope data flowdata flow
Virtual telescope
Simulation archive
Theory/observational
interface
Find possibly relevanthydro simulations(registry, dm, voql)
Observe selectedsimulations virtually
(application, services)
X-RayObservation
“Find similarsimulations”
Retrieve data (dal)
Feature Extractor
Registry service
ComparatorRetrieve data (dal) Analysis softawreAnalyse
Compare
Extract queriablefeatures (dm, ucd)
Retrieve telescopeconfiguration (dm)
2005-06-302005-06-30 RingbergRingberg, Gerard Lemson, Gerard Lemson
Quotes:Quotes:
"I think the global virtual observatory is a "I think the global virtual observatory is a fantastic idea" fantastic idea" - Martin Rees, Physics Today, Feb 2002- Martin Rees, Physics Today, Feb 2002
... too much money will be sunk into software; ... ... too much money will be sunk into software; ... archives at ground-based observatories should archives at ground-based observatories should be brought up to snuff before thinking about be brought up to snuff before thinking about linking them; and ... users won't be able to trust linking them; and ... users won't be able to trust the processed data they call up.“the processed data they call up.“ - Physics Today, Feb 2002 - Physics Today, Feb 2002
“… “… that VO nonsense …” that VO nonsense …” - anon, Ringberg 2005- anon, Ringberg 2005
2005-06-302005-06-30 RingbergRingberg, Gerard Lemson, Gerard Lemson
DiscussionDiscussion
What do you want from the VO ?What do you want from the VO ? What should VO projects focus on ?What should VO projects focus on ?
What could/do you contribute to the VO ?What could/do you contribute to the VO ? Why is the VO a waste of resources ?Why is the VO a waste of resources ?
Should spend money on more postdocs.Should spend money on more postdocs. What are the dangers of the VO?What are the dangers of the VO?
Too easy to do to bad science.Too easy to do to bad science. What are the possible advantages of the VO?What are the possible advantages of the VO?
Easier to do good, new science.Easier to do good, new science. Easy to check bad science.Easy to check bad science.