P1252428529vaeWs

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THE US NATIONAL VIRTUAL OBSERVATORY
NVO Science Overview for the NVO Science
Steering Committee
Alex Szalay, Dave De Young, Bob Hanisch US NVO
Project
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NVO History and Motivation
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History

• 1990s NASA establishes wavelength-oriented
  science archive centers multiple large
  ground-based digital sky survey projects
  initiated
• April 1999 Decadal Survey Panel on Theory,
  Computation, and Data Discovery meets in Los
  Alamos
• Szalay, Prince, and Alcock coin the name
  National Virtual Observatory
• November 1999 NVO organizational workshop at JHU
• February 2000 2nd NVO workshop at NOAO-Tucson
• June 2000, conference held at Caltech, Towards
  a Virtual Observatory
• June 2000 ad hoc Steering Committee formed
• February 2001 AASC/NAS report released
• April 2001 proposal submitted to NSF ITR - 17
  collaborating institutions
• September 2001 NSF announces proposal selection
• April 2002 joint NASA/NSF Science Definition
  Team submits report
• January 200, first NVO science prototypes shown
  at Seattle AAS

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Decadal Survey Recommendation

• National Academy of Sciences Decadal Survey
  recommended NVO as highest priority small
  (lt100M) project
• Several small initiatives recommended by the
  committee span both ground and space. The first
  among themthe National Virtual Observatory
  (NVO)is the committees top priority among the
  small initiatives. The NVO will provide a
  virtual sky based on the enormous data sets
  being created now and the even larger ones
  proposed for the future. It will enable a new
  mode of research for professional astronomers and
  will provide to the public an unparalleled
  opportunity for education and discovery.
• Astronomy and Astrophysics in the New
  Millennium, p. 14

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What the Virtual Observatory is

• A set of international standards to share complex
  data
• A modular set of tools to work with distributed
  data
• An essential part of the research astronomers
  toolkit
• A catalyst for world-wide access to astronomical
  archives
• A vehicle for education and public outreach
• NOT a replacement for building new telescopes and
  instruments
• NOT a centralized repository for data
• NOT a data quality enforcement organization

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International VO Alliance
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International VO Alliance

• The IVOA brings together the astronomers,
  developers, and managers of the VO initiatives
  world-wide
• Agreements on standards for data access (VOTable,
  catalog queries, image retrieval, resource
  descriptions, etc.)
• Coordination of development activities
• Sharing of software
• Sharing of experience
• 15 participating organizations Astrogrid, AVO,
  US-NVO, VO-Australia, VO-Canada, VO-China,
  VO-France, VO-Germany (GAVO), VO-Hungary,
  VO-India, VO-Italy (DRACO), VO-Japan, VO-Korea,
  VO-Russia, Spanish VO
• httpwww.ivoa.net

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NVO Science Steering Committee

• Recommended by NVO Advisory Committee December
  2003
• G. Gilmore, J.Huchra, S. Karin, R.Kennicutt, C.
  Lagoze,
• P. Messina, E. Ostriker, S. Wolff (Chair)
• It is now time to actively engage the user
  community in order to ensure acceptance and
  success. - NVO Advisory Committee Report
• SSC Membership D. De Young (Chair), G.
  Djorgovski, M. Donahue, M. Haynes
  (after 10/04), F. Hill, P. Pinto,
  J. Ulvestad, B. Wilkes

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NVO Science Steering Committee

• SSC Mandate
• Advise and assist the NVO in formulating science
  policies and objectives
• Near term and long term
• Advise the NVO on strategies to achieve these
  objectives
• Monitor progress of implementation plans
• Not a passive committee

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NVO Science Steering Committee

• Objectives of this meeting
• Familiarization with current NVO status and
  capabilities
• Review current Issues and problems faced
• Focus on strategy for engagement of scientific
  community
• Recommendations for near term efforts re
  January AAS meeting
• Other strategy recommendations short and long
  term

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NVO-Enabled Science
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Science Prototypes

• Science prototypes guide and validate technical
  initiatives
• NVO Year 1
• Brown dwarf candidate search
• Gamma-ray burst follow-up
• Galaxy morphology measurement (utilizing
  computational grid)
• Year 1.5
• Data Inventory Service
• Year 2
• Data Inventory Service with registry-based
  resource selection
• Access to theoretical simulation (globular
  cluster) and virtual observations
• European VO project
• Type 2 (obscured) quasars 40 new candidates
  found paper published in AA
• Galactic star formation regions
• Year 3 First robust science applications

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Data Inventory Service
Scientific Motivation Rapid collection of
multi-wavelength imaging, catalog and observation
data following an interesting transient event is
essential. This service can also be used as a
general tool to quickly access all data available
on any patch of sky for any science use.   Data
Resources Multi-wavelength data from any number
of sites (currently 13 different sites) sampling
energies from X-ray to radio, and including
images, object lists, and catalogues of
observations.   What the VO Brings Integration
and organization of a variety of data sources
into an easily comprehensible information set.
Scalability to an arbitrary number of data
providers. Integrates data with multiple data
visualization services.
Enabling Technologies Standard protocols to
remote services such as Cone Search and Simple
Image Access, standardized VOTables for data
retrieval transformation, and standardized
semantics encoded as Uniform Content Descriptors
(UCDs). Resource registry.   Future Prospects
Customization and quality control of resources
searched more sophisticated use of metadata.
 
Positions of HST and Chandra observations for
GRB010222
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Data Inventory Service
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Data Inventory Service
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Data Inventory Service
http//heasarc.gsfc.nasa.gov/vo/
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Brown Dwarf Candidate Search
Scientific Motivation The search for brown
dwarfs has been revolutionized by the latest deep
sky surveys. A key attribute to discovering brown
dwarfs is the federation of many surveys over
different wavelengths. Such matching of catalogs
is currently laborious and time consuming. This
matching problem is generic to many areas of
astrophysics. Data Resources Sloan Digital Sky
Survey (SDSS) Early Data Release (15 million
objects) 2-Micron All Sky Survey (2MASS) 2nd
Incremental Point Source Catalog (162 million
objects)
What the VO Brings Today, doing datasets is
user-intensive and is replicated by many
different users. Also, the correlation of these
two datasets can take years of CPU time if not
done correctly. The NVO brings two key aspects
to this problem. First, it removes the need for
the user to download large data to their machine,
making direct use of distributed data. Second,
the matching algorithm used here is
computationally efficient and designed to give
answers in minutes rather than hours results can
be returned to the user in real-time.
Sloan z magnitudes vs. 2MASS J magnitudes, with
brown dwarf candidates in red.  Data are from the
SDSS Early Data Release and 2MASS 2nd Incremental
Release.
Future Prospects Catalog matching of large
datasets is a generic problem in astrophysics.
Therefore, making the matching facility available
to any user for use on any dataset will greatly
enhance the productivity of scientists. Standard
I/O formats allow developers to create tools to
use the matched data and easily integrate with
existing visualization and analysis tools
(anomaly detector). Bringing these data together
on remote machines with enough CPU to perform
analysis (Grid technology) will allow
cross-comparisons of unprecedented scale.
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• As a T dwarf becomes cooler (i.e., methane and
  water absorptions increase) or more distant
• SDSS detects it only at z band
• 2MASS detects it only at J band

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Demo Leads to Discovery!

• New brown dwarf candidate confirmed
  spectroscopically with Keck Observatory

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Galaxy Morphology in Clusters
Scientific Motivation Investigate the dynamical
state of galaxy clusters and galaxy evolution
within the context of large-scale structure.  Use
galaxy morphology as a probe of dynamical history
by calculating, for each galaxy in a cluster
Surface brightness Concentration index
Asymmetry index These parameters are analyzed
with other indicators such as magnitude, color,
peculiar velocity, position in cluster, and
cluster large-scale structure. Data
Resources Computing Resources Chandra X-ray
image (SAO/CXC) USC/ISI ROSAT image
(GSFC/HEASARC) UW-Madison/NCSA DSS image
(STScI/MAST) Fermilab Galaxy cluster catalogs
(NED) CNOC1 cluster images and catalogs (CADC)
What the VO Brings Distributed data access and
Grid-based computing make possible for the first
time effective integration of multiple datasets
and real-time computing. Integration of data
from diverse sources is enabled by standardized
data objects and standardized remote computing
services. Flexibility of access means that
further NVO-compliant images and catalogs can be
added easily. Users can select their
visualization portal (Aladin, OASIS,
DS9). Enabling Technologies VOTable,
NVO-compliant catalog and image access, standard
semantics, Grid computing infrastructure.
Future Prospects Dynamic discovery and
selection of image, catalog, and computing
resources. User-selection of analysis tools and
ability to publish data to the NVO framework.
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Galaxy Morphology in Clusters
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Galaxy Morphology in Clusters
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Galaxy Morphology in Clusters
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Galaxy Morphology in Clusters
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Globular Cluster Simulations
http//bima.astro.umd.edu/cgi-bin/nemo/tvo3.pl
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Globular Cluster Simulations
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Spectral Database Browser
http//voservices.net/spectrum/
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Spectral Database Browser
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Spectral Database Browser
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Spectral Database Browser
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Spectral Database Browser
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Montage

• The Montage project will deploy a portable,
  compute-intensive service that will deliver
  science-grade custom mosaics on demand, with
  requests made through existing portals.
  Science-grade in this context requires that
  terrestrial and instrumental features are removed
  from images in a way that can be described
  quantitatively custom refers to user-specified
  parameters of projection, coordinates, size,
  rotation and spatial sampling.

http//montage.ipac.caltech.edu/
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AtlasMaker

• The Atlasmaker project is using Grid technology
  in combination with NVO interoperability to
  create new knowledge resources in astronomy. The
  product is a multi-faceted, multi-dimensional,
  scientifically trusted image atlas of the sky,
  made by federating many different surveys at
  different wavelengths, times, resolutions,
  polarizations, etc. Atlasmaker does resampling
  and mosaicking of image collections, and is
  well-suited to operate with the Hyperatlas
  standard. Requests can be satisfied via on-demand
  computations or by accessing a data cache.
  Computed data is stored in a distributed virtual
  file system, such as the Storage Resource Broker
  (SRB). We expect these atlases to be a new and
  powerful paradigm for knowledge extraction in
  astronomy, as well as a way to build educational
  resources. The system is being incorporated into
  the data analysis pipeline of the Palomar-Quest
  synoptic survey, and is being used to generate
  all-sky atlases from the 2MASS, SDSS, and DPOSS
  surveys for joint object detection.

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AtlasMaker HyperAtlas
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Resource Registry
http//nvo.stsci.edu/VORegistry/index.aspx
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Resource Registry
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Resource Registry
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Open Sky Query
http//openskyquery.net/Sky/skysite/default.aspx
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Open Sky Query
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Open Sky Query
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NVO Web Site

• Redesigned NVO web site with a focus on end-users
• Software tools/applications and data access
  services are easier to locate
• Application and service providers can provide
  their own documentation

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NVO Web Site
http//us-vo.org/
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Vision of Year3 Applications

• Take 5 simple core applications representing
  daily tasks of research astronomers
• Should be convincing for first time users
• Easy-to-use, robust services with clear
  documentation
• Focus on quality instead of feature creep
• Should all be based on VO standards
• Deploy in Q1 2005
• Templates/prototypes/docs and training for
  community
• Expect increasing number of community contributed
  tools

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Strawman List of Year3 Apps

• Queryable VO Registry
• Simple data access layer on most archives
  (SIAP,SSAP,Cone)
• OpenSkyNode access with most archives
  participating
• DIS service
• OpenSkyQuery
• Spectrum/bandpass service
• Dynamic image-to-catalog tool
• AtlasMaker
• These exist in prototype formList short enough
  to be comprehensible, achievable

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