AstroGrid:

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• AstroGrid
• The UK Virtual Observatory
• Elizabeth Auden and Silvia Dalla
• 12 June 2007, Denver, CO
• Virtual Observatories in Geosciences

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What is AstroGrid?
UK virtual observatory

• Consortium of several UK Universities, funded by
  PPARC to build a VO for the UK.
• Part of the Euro-VO www.euro-vo.org
• AstroGrid release 2007.1 www.astrogrid.org/la
  unch
• Data discovery, access to data and applications,
  visualization tools

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What is the virtual observatory?

• www.encyclopedia.com VO collection of
  integrated astronomical data archives and
  software tools that utilize computer networks to
  create an environment in which research can be
  conducted

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Why do we need a virtual observatory?

• Data volume doubles every year
• Increase of size and multiplex capabilities of
  new instruments
• WFCAM 100Gb/night (100Tb/yr)
• VISTA 300Gb/night (300Tb/yr)
• e-MERLIN/ALMA 1Tb/day
• SDO 1 Tb/day

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How does AstroGrid fit in the wider VO?
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IVOA Standards

• STC space / time / spectral metadata
• VOEvent who, what, where, when, why, and how of
  transient data
• ADQL Astronomical Data Query Language
• VORegistry and VOResource how to describe a data
  archive, remote application, processing resource,
  storage, or institution so that IVOA-compatible
  VO resources can find each other
• Full list http//www.ivoa.net/xml/index.html

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IVOA Working Drafts

• PLASTIC messaging protocol to send data (and
  metadata) between VO applications like data
  searching and visualization tools (TOPCAT,
  Aladin, VOSpec, etc)
• STAP Simple Time Access Protocol time-based
  queries of solar and STP data used by HelioScope
  tool
• Coming soon
• SEAP Simple Event Access Protocol
• VOTimeSeries encapsulation of time series data

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AstroGrid and solar VOs

• EGSO DSA module for Solar Event Catalogue
• VSO STAP services for SOHO-CDS, SOHO-EIT,
  SOHO-MDI, SOHO-LASCO, TRACE, and RHESSI image
  data
• CDAW STAP services for Voyager, Cluster, GOES,
  Ulysses, ACE, Wind spacecraft, and Polar
  spacecraft time series data

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What can I do with AstroGrid?

• Find data
• Simple searches AstroScope and HelioScope
• Complex searches workflow builder
• Analyse data
• Simple execution Task Launcher
• Complex execution workflow builder,
  parameterized workflows
• Store data remotely 
• Upload / download from MySpace, local disk, URLs

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AstroGrid goals

• Enable science by
• Improving the quality, easy, speed of on-line
  astronomy
• Making integration and comparison of data from
  diverse sources transparent
• Removing data access barriers to multiwavelength
  analysis
• Provide easy access to and manipulation of large
  datasets

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So, how does it work?

• 3 examples
• Astrophysics finding data with AstroScope,
  viewing images in Aladin, and manipulating
  catalogues with Topcat
• Solar physics parameterized workflow the solar
  movie maker and EIT data
• STP the task launcher and the CTIP modelling
  application

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AstroGrid Components

• Users Workbench
• AstroScope
• HelioScope
• Task Launcher
• Workflow builder
• MySpace

• Service providers
• CEA
• DSA
• Registry
• JES
• PLASTIC tools

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AstroGrid Components

• Access to database of observations via AG DSA
  (DataSet Access) software
• Requests are sent using ADQL (Astronomy Data
  Query Language), similar to SQL

DSA
Database of observations (at archive)
AG Workbench/ workflow engine
Input ADQL query
Output table of observations satisfying the
query, in VOTable format
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AstroGrid CEA

• Capability to call a set of processing routines
  that do operations on data, or a model (apps in
  any programming language can be wrapped) CEA
  Application

CEA
AG workbench/ workflow engine
Application. E.g. software that processes data,
model etc (on apps server)
Input CEA application input parameters
Output processed files saved to MySpace,
numerical / string parameters displayed to user
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AstroGrid Workbench

• Workbench gives access to AG services
• Data discovery AstroScope and HelioScope
• Task Launcher send query to a database or
  launch application
• Run a ready-made science workflow
• Build your own workflow with the Workflow Builder
• View your files in MySpace

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AstroGrid MySpace

• Virtual disk space where you can store
• Results
• temporary files
• query files
• workflow files
• You can adjust and re-run jobs on a later day.
• Visible from any computer.

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AstroGrid Registry

• How do you find the data you require?
• How do you decide which resource (data,
  application, information, disk, ) to use?
• The registries are the yellow pages for
  astronomical resources
• IVOA registries harvest each other thus querying
  any one returns full list of globally held
  resources.

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VOTable Format

• XML standard for the interchange of data
  represented as a set of tables
• A table is an unordered set of rows, as
  specified in the table metadata
• Each row is a sequence of table cells, each of
  them containing a primitive data type or an array
  of such primitives
• It bridges two ways to express structured data
  XML and FITS
• Use of Universal Column Descriptors (UCDs) to
  express the content of each parameter.

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AstroGrid Workflow

• Workflow capability so that queries to datasets
  and calls to applications can be managed
• Jobs are run remotely and asynchronously
• Queries and workflows can be re-used and shared
• AstroGrid is currently the only VO project with a
  workflow capability

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Workflow Example solar movie maker
Solar Movie Maker science workflow. Other
science workflows available Redshift Maker,
Colour Cutter, Cone Search, SWIRE images
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How to get started

• Apply for an AstroGrid account
• Email astrogrid_signup_at_star.le.ac.uk
• Include name, institution, department
• Download the workbench
• http//software.astrogrid.org/jnlp/workbench/workb
  ench.jnlp
• Try out
• AstroScope and HelioScope
• A science workflow
• An application from the task launcher
• Then start building complex workflows!

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AstroGrid contacts

• Technical help
• Help desk astrogrid_help_at_star.le.ac.uk
• Science team
• Solar / STP Silvia Dalla, s.dalla_at_manchester.ac.u
  k
• Galactic astronomy Anita Richards,
  amsr_at_jb.man.ac.uk
• Extra-galactic astronomy Eduardo
  Gonzalez-Solares, eglez_at_ast.cam.ac.uk

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Links

• AstroGrid home
• http//www.astrogrid.org
• Launch AstroGrid workbench
• http//www2.astrogrid.org/science/getting-started/
  
• AstroGrid software
• http//software.astrogrid.org/
• AstroGrid documentation
• http//www2.astrogrid.org/science/documentation

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Ongoing work

• VOExplorer New user interface with search and
  filter capabilities
• PLASTIC communication protocol that sends data
  between client-side search and analysis tools in
  the process of becoming an IVOA standard
• Taverna integration of UK client-side workflow
  builder
• Digital certificates increased security for VO
  storage, remote processing, and shared datasets
• Continuing integration of new datasets, analysis
  tools, and client-side applications

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AstroGrid Scientists and Developers

• Thanks to
• Alasdair Allan, Elizabeth Auden, Kona
  Andrews, Kevin Benson, Silvia Dalla, Gary
  Gilchrist, Eduardo Gonzalez, Norman Gray, Paul
  Harrison, Tony Linde, Jeff Lusted, Phil
  Nicholson, Keith Noddle, Jonathan Tedds, Dave
  Morris, Catherine Qin, Anita Richards, Guy Rixon,
  John Taylor, Mark Taylor, Nicholas Walton, Noel
  Winstanley